diff --git a/Cargo.lock b/Cargo.lock
index 2099055..bb95af9 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4541,6 +4541,17 @@ dependencies = [
  "tokio",
 ]
 
+[[package]]
+name = "omnigraph-api-types"
+version = "0.7.0"
+dependencies = [
+ "omnigraph-compiler",
+ "omnigraph-engine",
+ "serde",
+ "serde_json",
+ "utoipa",
+]
+
 [[package]]
 name = "omnigraph-cli"
 version = "0.7.0"
@@ -4674,6 +4685,7 @@ dependencies = [
  "futures",
  "lance",
  "lance-index",
+ "omnigraph-api-types",
  "omnigraph-cluster",
  "omnigraph-compiler",
  "omnigraph-engine",
diff --git a/Cargo.toml b/Cargo.toml
index 918ac05..76b37e0 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -4,6 +4,7 @@ members = [
     "crates/omnigraph-compiler",
     "crates/omnigraph",
     "crates/omnigraph-cli",
+    "crates/omnigraph-api-types",
     "crates/omnigraph-cluster",
     "crates/omnigraph-policy",
     "crates/omnigraph-server",
diff --git a/crates/omnigraph-api-types/Cargo.toml b/crates/omnigraph-api-types/Cargo.toml
new file mode 100644
index 0000000..d69d4fe
--- /dev/null
+++ b/crates/omnigraph-api-types/Cargo.toml
@@ -0,0 +1,16 @@
+[package]
+name = "omnigraph-api-types"
+version = "0.7.0"
+edition = "2024"
+description = "Shared HTTP wire DTOs for Omnigraph — request/response types and engine-result → DTO mappings used by both omnigraph-server and omnigraph-cli (RFC-009). Plain serde/utoipa types; no transport or server internals."
+license = "MIT"
+repository = "https://github.com/ModernRelay/omnigraph"
+homepage = "https://github.com/ModernRelay/omnigraph"
+documentation = "https://docs.rs/omnigraph-api-types"
+
+[dependencies]
+omnigraph = { package = "omnigraph-engine", path = "../omnigraph", version = "0.7.0" }
+omnigraph-compiler = { path = "../omnigraph-compiler", version = "0.7.0" }
+serde = { workspace = true }
+serde_json = { workspace = true }
+utoipa = { workspace = true }
diff --git a/crates/omnigraph-api-types/src/lib.rs b/crates/omnigraph-api-types/src/lib.rs
new file mode 100644
index 0000000..910d86b
--- /dev/null
+++ b/crates/omnigraph-api-types/src/lib.rs
@@ -0,0 +1,697 @@
+//! Shared HTTP wire DTOs (RFC-009 Phase 2) — moved from
+//! omnigraph-server's api module so server and CLI share one definition
+//! and one engine-result -> DTO mapping per verb. Plain serde/utoipa
+//! types; no transport, no server internals.
+
+use omnigraph::db::{GraphCommit, MergeOutcome, ReadTarget, SchemaApplyResult, Snapshot};
+use omnigraph::error::{MergeConflict, MergeConflictKind};
+use omnigraph::loader::{LoadMode, LoadResult};
+use omnigraph_compiler::SchemaMigrationStep;
+use omnigraph_compiler::query::ast::Param;
+use omnigraph_compiler::result::QueryResult;
+use omnigraph_compiler::types::{PropType, ScalarType};
+use serde::{Deserialize, Serialize};
+use serde_json::Value;
+use utoipa::{IntoParams, ToSchema};
+
+/// Shadow enum for documenting [`LoadMode`] in the OpenAPI schema.
+#[derive(ToSchema)]
+#[schema(as = LoadMode)]
+#[allow(dead_code)]
+enum LoadModeSchema {
+    /// Overwrite existing data.
+    #[schema(rename = "overwrite")]
+    Overwrite,
+    /// Append to existing data.
+    #[schema(rename = "append")]
+    Append,
+    /// Merge by id key (upsert).
+    #[schema(rename = "merge")]
+    Merge,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct SnapshotTableOutput {
+    pub table_key: String,
+    pub table_path: String,
+    pub table_version: u64,
+    pub table_branch: Option<String>,
+    pub row_count: u64,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct SnapshotOutput {
+    pub branch: String,
+    pub manifest_version: u64,
+    pub tables: Vec<SnapshotTableOutput>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct BranchCreateRequest {
+    /// Parent branch to fork from. Defaults to `main`.
+    pub from: Option<String>,
+    /// Name of the new branch. Must not already exist.
+    pub name: String,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct BranchCreateOutput {
+    pub uri: String,
+    pub from: String,
+    pub name: String,
+    pub actor_id: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct BranchListOutput {
+    pub branches: Vec<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct BranchDeleteOutput {
+    pub uri: String,
+    pub name: String,
+    pub actor_id: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct BranchMergeRequest {
+    /// Source branch whose commits will be merged.
+    pub source: String,
+    /// Target branch that will receive the merge. Defaults to `main`.
+    pub target: Option<String>,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, ToSchema)]
+#[serde(rename_all = "snake_case")]
+pub enum BranchMergeOutcome {
+    AlreadyUpToDate,
+    FastForward,
+    Merged,
+}
+
+impl From<MergeOutcome> for BranchMergeOutcome {
+    fn from(value: MergeOutcome) -> Self {
+        match value {
+            MergeOutcome::AlreadyUpToDate => Self::AlreadyUpToDate,
+            MergeOutcome::FastForward => Self::FastForward,
+            MergeOutcome::Merged => Self::Merged,
+        }
+    }
+}
+
+impl BranchMergeOutcome {
+    pub fn as_str(self) -> &'static str {
+        match self {
+            Self::AlreadyUpToDate => "already_up_to_date",
+            Self::FastForward => "fast_forward",
+            Self::Merged => "merged",
+        }
+    }
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct BranchMergeOutput {
+    pub source: String,
+    pub target: String,
+    pub outcome: BranchMergeOutcome,
+    pub actor_id: Option<String>,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, ToSchema)]
+#[serde(rename_all = "snake_case")]
+pub enum MergeConflictKindOutput {
+    DivergentInsert,
+    DivergentUpdate,
+    DeleteVsUpdate,
+    OrphanEdge,
+    UniqueViolation,
+    CardinalityViolation,
+    ValueConstraintViolation,
+}
+
+impl MergeConflictKindOutput {
+    pub fn as_str(self) -> &'static str {
+        match self {
+            Self::DivergentInsert => "divergent_insert",
+            Self::DivergentUpdate => "divergent_update",
+            Self::DeleteVsUpdate => "delete_vs_update",
+            Self::OrphanEdge => "orphan_edge",
+            Self::UniqueViolation => "unique_violation",
+            Self::CardinalityViolation => "cardinality_violation",
+            Self::ValueConstraintViolation => "value_constraint_violation",
+        }
+    }
+}
+
+impl From<MergeConflictKind> for MergeConflictKindOutput {
+    fn from(value: MergeConflictKind) -> Self {
+        match value {
+            MergeConflictKind::DivergentInsert => Self::DivergentInsert,
+            MergeConflictKind::DivergentUpdate => Self::DivergentUpdate,
+            MergeConflictKind::DeleteVsUpdate => Self::DeleteVsUpdate,
+            MergeConflictKind::OrphanEdge => Self::OrphanEdge,
+            MergeConflictKind::UniqueViolation => Self::UniqueViolation,
+            MergeConflictKind::CardinalityViolation => Self::CardinalityViolation,
+            MergeConflictKind::ValueConstraintViolation => Self::ValueConstraintViolation,
+        }
+    }
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct MergeConflictOutput {
+    pub table_key: String,
+    pub row_id: Option<String>,
+    pub kind: MergeConflictKindOutput,
+    pub message: String,
+}
+
+impl From<&MergeConflict> for MergeConflictOutput {
+    fn from(value: &MergeConflict) -> Self {
+        Self {
+            table_key: value.table_key.clone(),
+            row_id: value.row_id.clone(),
+            kind: value.kind.into(),
+            message: value.message.clone(),
+        }
+    }
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct ReadTargetOutput {
+    pub branch: Option<String>,
+    pub snapshot: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct ReadOutput {
+    pub query_name: String,
+    pub target: ReadTargetOutput,
+    pub row_count: usize,
+    #[serde(default, skip_serializing_if = "Vec::is_empty")]
+    pub columns: Vec<String>,
+    pub rows: Value,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct ChangeOutput {
+    pub branch: String,
+    pub query_name: String,
+    pub affected_nodes: usize,
+    pub affected_edges: usize,
+    pub actor_id: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct IngestTableOutput {
+    pub table_key: String,
+    pub rows_loaded: usize,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct IngestOutput {
+    pub uri: String,
+    pub branch: String,
+    /// Base branch a fork was requested from (the request's `from`), echoed
+    /// even when the branch already existed. `null` when `from` was absent.
+    pub base_branch: Option<String>,
+    pub branch_created: bool,
+    #[schema(value_type = LoadModeSchema)]
+    pub mode: LoadMode,
+    pub tables: Vec<IngestTableOutput>,
+    pub actor_id: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct CommitOutput {
+    pub graph_commit_id: String,
+    pub manifest_branch: Option<String>,
+    pub manifest_version: u64,
+    pub parent_commit_id: Option<String>,
+    pub merged_parent_commit_id: Option<String>,
+    pub actor_id: Option<String>,
+    /// Commit creation time as Unix epoch microseconds.
+    #[schema(example = 1714000000000000i64)]
+    pub created_at: i64,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct CommitListOutput {
+    pub commits: Vec<CommitOutput>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct ReadRequest {
+    /// GQ query source. May declare one or more named queries; pick one with
+    /// `query_name` if there is more than one.
+    #[schema(
+        example = "query get_person($name: String) {\n    match {\n        $p: Person { name: $name }\n    }\n    return { $p.name, $p.age }\n}"
+    )]
+    pub query_source: String,
+    /// Name of the query to run when `query_source` declares multiple. Optional
+    /// when only one query is declared.
+    pub query_name: Option<String>,
+    /// JSON object whose keys match the query's declared parameters.
+    pub params: Option<Value>,
+    /// Branch to read from. Mutually exclusive with `snapshot`. Defaults to `main`.
+    pub branch: Option<String>,
+    /// Snapshot id to read from. Mutually exclusive with `branch`.
+    pub snapshot: Option<String>,
+}
+
+/// Inline read-query request for `POST /query`.
+///
+/// Friendlier-named alternative to [`ReadRequest`] for ad-hoc reads and
+/// AI-agent integration. Mutations are rejected with 400 — use `POST
+/// /mutate` (or its deprecated alias `POST /change`) for write queries.
+/// Field names are deliberately short (`query`, `name`) to match the GQ
+/// keyword and the CLI `-e` flag.
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct QueryRequest {
+    /// GQ read-query source. May declare one or more named queries; pick one
+    /// with `name` when more than one is declared. Mutations
+    /// (`insert`/`update`/`delete`) get 400 — use `POST /mutate` (or its
+    /// deprecated alias `POST /change`) instead.
+    #[schema(example = "query get_person($name: String) {\n    match {\n        $p: Person { name: $name }\n    }\n    return { $p.name, $p.age }\n}")]
+    pub query: String,
+    /// Name of the query to run when `query` declares multiple. Optional when
+    /// only one query is declared.
+    pub name: Option<String>,
+    /// JSON object whose keys match the query's declared parameters.
+    pub params: Option<Value>,
+    /// Branch to read from. Mutually exclusive with `snapshot`. Defaults to `main`.
+    pub branch: Option<String>,
+    /// Snapshot id to read from. Mutually exclusive with `branch`.
+    pub snapshot: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct ChangeRequest {
+    /// GQ mutation source containing `insert`, `update`, or `delete` statements.
+    /// May declare multiple named mutations; pick one with `name`.
+    ///
+    /// Accepts the legacy field name `query_source` as a deserialization alias.
+    #[schema(
+        example = "query insert_person($name: String, $age: I32) {\n    insert Person { name: $name, age: $age }\n}"
+    )]
+    #[serde(alias = "query_source")]
+    pub query: String,
+    /// Name of the mutation to run when `query` declares multiple.
+    ///
+    /// Accepts the legacy field name `query_name` as a deserialization alias.
+    #[serde(default, alias = "query_name")]
+    pub name: Option<String>,
+    /// JSON object whose keys match the mutation's declared parameters.
+    #[serde(default)]
+    pub params: Option<Value>,
+    /// Target branch. Defaults to `main`.
+    #[serde(default)]
+    pub branch: Option<String>,
+}
+
+/// Body for `POST /queries/{name}` — invokes the server-side stored query
+/// named in the path. The query source and name come from the registry,
+/// never the body; only the runtime inputs are supplied here.
+#[derive(Debug, Clone, Default, Serialize, Deserialize, ToSchema)]
+pub struct InvokeStoredQueryRequest {
+    /// JSON object whose keys match the stored query's declared parameters.
+    #[serde(default)]
+    pub params: Option<Value>,
+    /// Branch to run against. Defaults to `main`; for a stored mutation the
+    /// write targets this branch.
+    #[serde(default)]
+    pub branch: Option<String>,
+    /// Snapshot id to read from (read queries only — rejected for a stored
+    /// mutation). Mutually exclusive with `branch`.
+    #[serde(default)]
+    pub snapshot: Option<String>,
+}
+
+/// Response for `POST /queries/{name}`: the read envelope for a stored
+/// read, or the mutation envelope for a stored mutation. Serialized
+/// **untagged**, so the wire shape is exactly [`ReadOutput`] or
+/// [`ChangeOutput`] — classification follows the stored query, not a
+/// wrapper field.
+#[derive(Debug, Serialize, ToSchema)]
+#[serde(untagged)]
+pub enum InvokeStoredQueryResponse {
+    Read(ReadOutput),
+    Change(ChangeOutput),
+}
+
+/// The kind of a stored-query parameter, decomposed so a client (e.g. an
+/// MCP server) can build a typed input schema with a closed `match` and
+/// never re-parse omnigraph's type spelling. `bigint`/`date`/`datetime`/
+/// `blob` are carried as JSON strings on the wire: a 64-bit integer past
+/// 2^53 loses precision as a JSON number, and Date/DateTime are ISO
+/// strings, Blob a blob-URI string.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, ToSchema)]
+#[serde(rename_all = "snake_case")]
+pub enum ParamKind {
+    String,
+    Bool,
+    Int,
+    #[serde(rename = "bigint")]
+    BigInt,
+    Float,
+    Date,
+    #[serde(rename = "datetime")]
+    DateTime,
+    Blob,
+    Vector,
+    List,
+}
+
+/// One declared parameter of a stored query, projected for the catalog.
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct ParamDescriptor {
+    pub name: String,
+    pub kind: ParamKind,
+    /// Element kind when `kind == list` (always a scalar — the grammar
+    /// forbids lists of vectors or nested lists).
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub item_kind: Option<ParamKind>,
+    /// Dimension when `kind == vector`.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub vector_dim: Option<u32>,
+    /// `false` → the caller must supply it; `true` → optional.
+    pub nullable: bool,
+}
+
+/// One entry in the stored-query catalog (`GET /queries`).
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct QueryCatalogEntry {
+    /// Registry key / invoke path segment (`POST /queries/{name}`).
+    pub name: String,
+    /// MCP tool id (the `tool_name` override, else `name`).
+    pub tool_name: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub description: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub instruction: Option<String>,
+    /// `true` for a stored mutation → an MCP read-only hint of `false`.
+    pub mutation: bool,
+    pub params: Vec<ParamDescriptor>,
+}
+
+/// Response for `GET /queries`: the `mcp.expose` subset of a graph's
+/// stored-query registry, each with typed parameters.
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct QueriesCatalogOutput {
+    pub queries: Vec<QueryCatalogEntry>,
+}
+
+/// Total map from a resolved scalar to its catalog kind. Exhaustive on
+/// purpose: a new `ScalarType` is a compile error here until catalogued.
+fn scalar_kind(scalar: ScalarType) -> ParamKind {
+    match scalar {
+        ScalarType::String => ParamKind::String,
+        ScalarType::Bool => ParamKind::Bool,
+        ScalarType::I32 | ScalarType::U32 => ParamKind::Int,
+        ScalarType::I64 | ScalarType::U64 => ParamKind::BigInt,
+        ScalarType::F32 | ScalarType::F64 => ParamKind::Float,
+        ScalarType::Date => ParamKind::Date,
+        ScalarType::DateTime => ParamKind::DateTime,
+        ScalarType::Blob => ParamKind::Blob,
+        ScalarType::Vector(_) => ParamKind::Vector,
+    }
+}
+
+pub fn param_descriptor(param: &Param) -> ParamDescriptor {
+    match PropType::from_param_type_name(&param.type_name, param.nullable) {
+        Some(pt) if pt.list => ParamDescriptor {
+            name: param.name.clone(),
+            kind: ParamKind::List,
+            item_kind: Some(scalar_kind(pt.scalar)),
+            vector_dim: None,
+            nullable: param.nullable,
+        },
+        Some(pt) => {
+            let (kind, vector_dim) = match pt.scalar {
+                ScalarType::Vector(dim) => (ParamKind::Vector, Some(dim)),
+                other => (scalar_kind(other), None),
+            };
+            ParamDescriptor {
+                name: param.name.clone(),
+                kind,
+                item_kind: None,
+                vector_dim,
+                nullable: param.nullable,
+            }
+        }
+        // Unreachable for a parsed query (every declared param type is
+        // grammatical); fall back to an opaque string so the field is still
+        // usable rather than dropped.
+        None => ParamDescriptor {
+            name: param.name.clone(),
+            kind: ParamKind::String,
+            item_kind: None,
+            vector_dim: None,
+            nullable: param.nullable,
+        },
+    }
+}
+
+
+#[derive(Debug, Clone, Default, Serialize, Deserialize, ToSchema)]
+pub struct SchemaApplyRequest {
+    /// Project schema in `.pg` source form. The diff against the current
+    /// schema produces the migration steps that will be applied.
+    #[schema(
+        example = "node Person {\n    name: String @key\n    age: I32?\n}\n\nedge Knows: Person -> Person"
+    )]
+    pub schema_source: String,
+    /// When true, promote every `DropMode::Soft` step in the plan to
+    /// `DropMode::Hard`, making the prior column data unreachable
+    /// after the apply. Matches the CLI's `--allow-data-loss` flag.
+    /// Defaults to `false` (drops remain reversible via time travel).
+    #[serde(default)]
+    pub allow_data_loss: bool,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct SchemaApplyOutput {
+    pub uri: String,
+    pub supported: bool,
+    pub applied: bool,
+    pub step_count: usize,
+    pub manifest_version: u64,
+    #[schema(value_type = Vec<Value>)]
+    pub steps: Vec<SchemaMigrationStep>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct SchemaOutput {
+    pub schema_source: String,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct IngestRequest {
+    /// Target branch. Defaults to `main`. Without `from`, the branch must
+    /// already exist — a missing branch is a 404, never an implicit fork.
+    pub branch: Option<String>,
+    /// Parent branch used to create `branch` if it does not exist. Branch
+    /// creation is opt-in by presence of this field; omit it to require an
+    /// existing branch.
+    pub from: Option<String>,
+    /// How existing rows are handled. Defaults to `merge`.
+    #[schema(value_type = Option<LoadModeSchema>)]
+    pub mode: Option<LoadMode>,
+    /// NDJSON payload: one record per line, each shaped
+    /// `{"type": "<TypeName>", "data": {...}}`.
+    #[schema(
+        example = "{\"type\": \"Person\", \"data\": {\"name\": \"Alice\", \"age\": 30}}\n{\"type\": \"Person\", \"data\": {\"name\": \"Bob\", \"age\": 25}}"
+    )]
+    pub data: String,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct ExportRequest {
+    /// Branch to export. Defaults to `main`.
+    pub branch: Option<String>,
+    /// Restrict the export to these node/edge type names. Empty exports all types.
+    #[serde(default)]
+    pub type_names: Vec<String>,
+    /// Restrict the export to these table keys. Empty exports all tables.
+    #[serde(default)]
+    pub table_keys: Vec<String>,
+}
+
+#[derive(Debug, Clone, Deserialize, IntoParams)]
+pub struct SnapshotQuery {
+    pub branch: Option<String>,
+}
+
+#[derive(Debug, Clone, Deserialize, IntoParams)]
+pub struct CommitListQuery {
+    pub branch: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct HealthOutput {
+    pub status: String,
+    pub version: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub source_version: Option<String>,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, ToSchema)]
+#[serde(rename_all = "snake_case")]
+pub enum ErrorCode {
+    Unauthorized,
+    Forbidden,
+    BadRequest,
+    NotFound,
+    /// 405 Method Not Allowed — the route exists but the active server
+    /// mode doesn't serve this method (e.g. `GET /graphs` in single-graph
+    /// mode). Distinct from 404 so clients can tell "wrong context" from
+    /// "no such resource."
+    MethodNotAllowed,
+    Conflict,
+    /// 429 Too Many Requests — per-actor admission cap exceeded.
+    /// Clients should respect the `Retry-After` header.
+    TooManyRequests,
+    Internal,
+}
+
+/// Structured details for a publisher-level OCC failure. Surfaces alongside
+/// HTTP 409 when a write was rejected because the caller's pre-write view of
+/// one table's manifest version was stale relative to the current head. The
+/// expected/actual fields tell the client which table to refresh.
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct ManifestConflictOutput {
+    pub table_key: String,
+    pub expected: u64,
+    pub actual: u64,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct ErrorOutput {
+    pub error: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub code: Option<ErrorCode>,
+    #[serde(default, skip_serializing_if = "Vec::is_empty")]
+    pub merge_conflicts: Vec<MergeConflictOutput>,
+    /// Set when the conflict is a publisher CAS rejection
+    /// (`ManifestConflictDetails::ExpectedVersionMismatch`). The caller's
+    /// pre-write view of `table_key` was at version `expected` but the
+    /// manifest is now at `actual`. Refresh and retry.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub manifest_conflict: Option<ManifestConflictOutput>,
+}
+
+pub fn snapshot_payload(branch: &str, snapshot: &Snapshot) -> SnapshotOutput {
+    let mut entries: Vec<_> = snapshot.entries().cloned().collect();
+    entries.sort_by(|a, b| a.table_key.cmp(&b.table_key));
+    let tables = entries
+        .iter()
+        .map(|entry| SnapshotTableOutput {
+            table_key: entry.table_key.clone(),
+            table_path: entry.table_path.clone(),
+            table_version: entry.table_version,
+            table_branch: entry.table_branch.clone(),
+            row_count: entry.row_count,
+        })
+        .collect::<Vec<_>>();
+    SnapshotOutput {
+        branch: branch.to_string(),
+        manifest_version: snapshot.version(),
+        tables,
+    }
+}
+
+pub fn schema_apply_output(uri: &str, result: SchemaApplyResult) -> SchemaApplyOutput {
+    SchemaApplyOutput {
+        uri: uri.to_string(),
+        supported: result.supported,
+        applied: result.applied,
+        step_count: result.steps.len(),
+        manifest_version: result.manifest_version,
+        steps: result.steps,
+    }
+}
+
+pub fn commit_output(commit: &GraphCommit) -> CommitOutput {
+    CommitOutput {
+        graph_commit_id: commit.graph_commit_id.clone(),
+        manifest_branch: commit.manifest_branch.clone(),
+        manifest_version: commit.manifest_version,
+        parent_commit_id: commit.parent_commit_id.clone(),
+        merged_parent_commit_id: commit.merged_parent_commit_id.clone(),
+        actor_id: commit.actor_id.clone(),
+        created_at: commit.created_at,
+    }
+}
+
+pub fn read_output(query_name: String, target: &ReadTarget, result: QueryResult) -> ReadOutput {
+    let columns = result
+        .schema()
+        .fields()
+        .iter()
+        .map(|field| field.name().clone())
+        .collect();
+    ReadOutput {
+        query_name,
+        target: read_target_output(target),
+        row_count: result.num_rows(),
+        columns,
+        rows: result.to_rust_json(),
+    }
+}
+
+pub fn ingest_output(
+    uri: &str,
+    result: &LoadResult,
+    mode: LoadMode,
+    actor_id: Option<String>,
+) -> IngestOutput {
+    IngestOutput {
+        uri: uri.to_string(),
+        branch: result.branch.clone(),
+        base_branch: result.base_branch.clone(),
+        branch_created: result.branch_created,
+        mode,
+        tables: result
+            .to_ingest_tables()
+            .into_iter()
+            .map(|table| IngestTableOutput {
+                table_key: table.table_key,
+                rows_loaded: table.rows_loaded,
+            })
+            .collect(),
+        actor_id,
+    }
+}
+
+pub fn read_target_output(target: &ReadTarget) -> ReadTargetOutput {
+    match target {
+        ReadTarget::Branch(branch) => ReadTargetOutput {
+            branch: Some(branch.clone()),
+            snapshot: None,
+        },
+        ReadTarget::Snapshot(snapshot) => ReadTargetOutput {
+            branch: None,
+            snapshot: Some(snapshot.as_str().to_string()),
+        },
+    }
+}
+
+// ─── MR-668 — management endpoint shapes ──────────────────────────────────
+
+/// One entry in the response from `GET /graphs`. Cluster operators
+/// consume this list to discover which graphs the server is currently
+/// serving. The shape is intentionally minimal — `graph_id` and `uri`
+/// are the only fields a routing client needs.
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct GraphInfo {
+    pub graph_id: String,
+    pub uri: String,
+}
+
+/// Response from `GET /graphs`. Lists every graph registered with the
+/// server in alphabetical order by `graph_id` (sorted server-side so
+/// clients get deterministic output across requests).
+#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
+pub struct GraphListResponse {
+    pub graphs: Vec<GraphInfo>,
+}
diff --git a/crates/omnigraph-server/Cargo.toml b/crates/omnigraph-server/Cargo.toml
index 614711e..a6a0717 100644
--- a/crates/omnigraph-server/Cargo.toml
+++ b/crates/omnigraph-server/Cargo.toml
@@ -22,6 +22,7 @@ aws = ["dep:aws-config", "dep:aws-sdk-secretsmanager"]
 omnigraph = { package = "omnigraph-engine", path = "../omnigraph", version = "0.7.0" }
 omnigraph-compiler = { path = "../omnigraph-compiler", version = "0.7.0" }
 omnigraph-policy = { path = "../omnigraph-policy", version = "0.7.0" }
+omnigraph-api-types = { path = "../omnigraph-api-types", version = "0.7.0" }
 omnigraph-cluster = { path = "../omnigraph-cluster", version = "0.7.0" }
 axum = { workspace = true }
 clap = { workspace = true }
diff --git a/crates/omnigraph-server/src/api.rs b/crates/omnigraph-server/src/api.rs
index ff3cf67..cf0d604 100644
--- a/crates/omnigraph-server/src/api.rs
+++ b/crates/omnigraph-server/src/api.rs
@@ -1,452 +1,14 @@
-use omnigraph::db::{GraphCommit, MergeOutcome, ReadTarget, SchemaApplyResult, Snapshot};
-use omnigraph::error::{MergeConflict, MergeConflictKind};
-use omnigraph::loader::{LoadMode, LoadResult};
+//! HTTP wire DTOs. The types and their engine-result -> DTO mappings live
+//! in the shared `omnigraph-api-types` crate (RFC-009 Phase 2) so the CLI
+//! and server share one definition; re-exported here so every
+//! `omnigraph_server::api::*` path (handlers, the OpenApi schema list,
+//! CLI imports) keeps resolving unchanged. Only `query_catalog_entry`
+//! stays — it maps the server's runtime `StoredQuery` (not a wire type)
+//! into the shared `QueryCatalogEntry` DTO.
+
+pub use omnigraph_api_types::*;
+
 use crate::queries::StoredQuery;
-use omnigraph_compiler::SchemaMigrationStep;
-use omnigraph_compiler::query::ast::Param;
-use omnigraph_compiler::result::QueryResult;
-use omnigraph_compiler::types::{PropType, ScalarType};
-use serde::{Deserialize, Serialize};
-use serde_json::Value;
-use utoipa::{IntoParams, ToSchema};
-
-/// Shadow enum for documenting [`LoadMode`] in the OpenAPI schema.
-#[derive(ToSchema)]
-#[schema(as = LoadMode)]
-#[allow(dead_code)]
-enum LoadModeSchema {
-    /// Overwrite existing data.
-    #[schema(rename = "overwrite")]
-    Overwrite,
-    /// Append to existing data.
-    #[schema(rename = "append")]
-    Append,
-    /// Merge by id key (upsert).
-    #[schema(rename = "merge")]
-    Merge,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct SnapshotTableOutput {
-    pub table_key: String,
-    pub table_path: String,
-    pub table_version: u64,
-    pub table_branch: Option<String>,
-    pub row_count: u64,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct SnapshotOutput {
-    pub branch: String,
-    pub manifest_version: u64,
-    pub tables: Vec<SnapshotTableOutput>,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct BranchCreateRequest {
-    /// Parent branch to fork from. Defaults to `main`.
-    pub from: Option<String>,
-    /// Name of the new branch. Must not already exist.
-    pub name: String,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct BranchCreateOutput {
-    pub uri: String,
-    pub from: String,
-    pub name: String,
-    pub actor_id: Option<String>,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct BranchListOutput {
-    pub branches: Vec<String>,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct BranchDeleteOutput {
-    pub uri: String,
-    pub name: String,
-    pub actor_id: Option<String>,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct BranchMergeRequest {
-    /// Source branch whose commits will be merged.
-    pub source: String,
-    /// Target branch that will receive the merge. Defaults to `main`.
-    pub target: Option<String>,
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, ToSchema)]
-#[serde(rename_all = "snake_case")]
-pub enum BranchMergeOutcome {
-    AlreadyUpToDate,
-    FastForward,
-    Merged,
-}
-
-impl From<MergeOutcome> for BranchMergeOutcome {
-    fn from(value: MergeOutcome) -> Self {
-        match value {
-            MergeOutcome::AlreadyUpToDate => Self::AlreadyUpToDate,
-            MergeOutcome::FastForward => Self::FastForward,
-            MergeOutcome::Merged => Self::Merged,
-        }
-    }
-}
-
-impl BranchMergeOutcome {
-    pub fn as_str(self) -> &'static str {
-        match self {
-            Self::AlreadyUpToDate => "already_up_to_date",
-            Self::FastForward => "fast_forward",
-            Self::Merged => "merged",
-        }
-    }
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct BranchMergeOutput {
-    pub source: String,
-    pub target: String,
-    pub outcome: BranchMergeOutcome,
-    pub actor_id: Option<String>,
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, ToSchema)]
-#[serde(rename_all = "snake_case")]
-pub enum MergeConflictKindOutput {
-    DivergentInsert,
-    DivergentUpdate,
-    DeleteVsUpdate,
-    OrphanEdge,
-    UniqueViolation,
-    CardinalityViolation,
-    ValueConstraintViolation,
-}
-
-impl MergeConflictKindOutput {
-    pub fn as_str(self) -> &'static str {
-        match self {
-            Self::DivergentInsert => "divergent_insert",
-            Self::DivergentUpdate => "divergent_update",
-            Self::DeleteVsUpdate => "delete_vs_update",
-            Self::OrphanEdge => "orphan_edge",
-            Self::UniqueViolation => "unique_violation",
-            Self::CardinalityViolation => "cardinality_violation",
-            Self::ValueConstraintViolation => "value_constraint_violation",
-        }
-    }
-}
-
-impl From<MergeConflictKind> for MergeConflictKindOutput {
-    fn from(value: MergeConflictKind) -> Self {
-        match value {
-            MergeConflictKind::DivergentInsert => Self::DivergentInsert,
-            MergeConflictKind::DivergentUpdate => Self::DivergentUpdate,
-            MergeConflictKind::DeleteVsUpdate => Self::DeleteVsUpdate,
-            MergeConflictKind::OrphanEdge => Self::OrphanEdge,
-            MergeConflictKind::UniqueViolation => Self::UniqueViolation,
-            MergeConflictKind::CardinalityViolation => Self::CardinalityViolation,
-            MergeConflictKind::ValueConstraintViolation => Self::ValueConstraintViolation,
-        }
-    }
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct MergeConflictOutput {
-    pub table_key: String,
-    pub row_id: Option<String>,
-    pub kind: MergeConflictKindOutput,
-    pub message: String,
-}
-
-impl From<&MergeConflict> for MergeConflictOutput {
-    fn from(value: &MergeConflict) -> Self {
-        Self {
-            table_key: value.table_key.clone(),
-            row_id: value.row_id.clone(),
-            kind: value.kind.into(),
-            message: value.message.clone(),
-        }
-    }
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct ReadTargetOutput {
-    pub branch: Option<String>,
-    pub snapshot: Option<String>,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct ReadOutput {
-    pub query_name: String,
-    pub target: ReadTargetOutput,
-    pub row_count: usize,
-    #[serde(default, skip_serializing_if = "Vec::is_empty")]
-    pub columns: Vec<String>,
-    pub rows: Value,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct ChangeOutput {
-    pub branch: String,
-    pub query_name: String,
-    pub affected_nodes: usize,
-    pub affected_edges: usize,
-    pub actor_id: Option<String>,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct IngestTableOutput {
-    pub table_key: String,
-    pub rows_loaded: usize,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct IngestOutput {
-    pub uri: String,
-    pub branch: String,
-    /// Base branch a fork was requested from (the request's `from`), echoed
-    /// even when the branch already existed. `null` when `from` was absent.
-    pub base_branch: Option<String>,
-    pub branch_created: bool,
-    #[schema(value_type = LoadModeSchema)]
-    pub mode: LoadMode,
-    pub tables: Vec<IngestTableOutput>,
-    pub actor_id: Option<String>,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct CommitOutput {
-    pub graph_commit_id: String,
-    pub manifest_branch: Option<String>,
-    pub manifest_version: u64,
-    pub parent_commit_id: Option<String>,
-    pub merged_parent_commit_id: Option<String>,
-    pub actor_id: Option<String>,
-    /// Commit creation time as Unix epoch microseconds.
-    #[schema(example = 1714000000000000i64)]
-    pub created_at: i64,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct CommitListOutput {
-    pub commits: Vec<CommitOutput>,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct ReadRequest {
-    /// GQ query source. May declare one or more named queries; pick one with
-    /// `query_name` if there is more than one.
-    #[schema(
-        example = "query get_person($name: String) {\n    match {\n        $p: Person { name: $name }\n    }\n    return { $p.name, $p.age }\n}"
-    )]
-    pub query_source: String,
-    /// Name of the query to run when `query_source` declares multiple. Optional
-    /// when only one query is declared.
-    pub query_name: Option<String>,
-    /// JSON object whose keys match the query's declared parameters.
-    pub params: Option<Value>,
-    /// Branch to read from. Mutually exclusive with `snapshot`. Defaults to `main`.
-    pub branch: Option<String>,
-    /// Snapshot id to read from. Mutually exclusive with `branch`.
-    pub snapshot: Option<String>,
-}
-
-/// Inline read-query request for `POST /query`.
-///
-/// Friendlier-named alternative to [`ReadRequest`] for ad-hoc reads and
-/// AI-agent integration. Mutations are rejected with 400 — use `POST
-/// /mutate` (or its deprecated alias `POST /change`) for write queries.
-/// Field names are deliberately short (`query`, `name`) to match the GQ
-/// keyword and the CLI `-e` flag.
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct QueryRequest {
-    /// GQ read-query source. May declare one or more named queries; pick one
-    /// with `name` when more than one is declared. Mutations
-    /// (`insert`/`update`/`delete`) get 400 — use `POST /mutate` (or its
-    /// deprecated alias `POST /change`) instead.
-    #[schema(example = "query get_person($name: String) {\n    match {\n        $p: Person { name: $name }\n    }\n    return { $p.name, $p.age }\n}")]
-    pub query: String,
-    /// Name of the query to run when `query` declares multiple. Optional when
-    /// only one query is declared.
-    pub name: Option<String>,
-    /// JSON object whose keys match the query's declared parameters.
-    pub params: Option<Value>,
-    /// Branch to read from. Mutually exclusive with `snapshot`. Defaults to `main`.
-    pub branch: Option<String>,
-    /// Snapshot id to read from. Mutually exclusive with `branch`.
-    pub snapshot: Option<String>,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct ChangeRequest {
-    /// GQ mutation source containing `insert`, `update`, or `delete` statements.
-    /// May declare multiple named mutations; pick one with `name`.
-    ///
-    /// Accepts the legacy field name `query_source` as a deserialization alias.
-    #[schema(
-        example = "query insert_person($name: String, $age: I32) {\n    insert Person { name: $name, age: $age }\n}"
-    )]
-    #[serde(alias = "query_source")]
-    pub query: String,
-    /// Name of the mutation to run when `query` declares multiple.
-    ///
-    /// Accepts the legacy field name `query_name` as a deserialization alias.
-    #[serde(default, alias = "query_name")]
-    pub name: Option<String>,
-    /// JSON object whose keys match the mutation's declared parameters.
-    #[serde(default)]
-    pub params: Option<Value>,
-    /// Target branch. Defaults to `main`.
-    #[serde(default)]
-    pub branch: Option<String>,
-}
-
-/// Body for `POST /queries/{name}` — invokes the server-side stored query
-/// named in the path. The query source and name come from the registry,
-/// never the body; only the runtime inputs are supplied here.
-#[derive(Debug, Clone, Default, Serialize, Deserialize, ToSchema)]
-pub struct InvokeStoredQueryRequest {
-    /// JSON object whose keys match the stored query's declared parameters.
-    #[serde(default)]
-    pub params: Option<Value>,
-    /// Branch to run against. Defaults to `main`; for a stored mutation the
-    /// write targets this branch.
-    #[serde(default)]
-    pub branch: Option<String>,
-    /// Snapshot id to read from (read queries only — rejected for a stored
-    /// mutation). Mutually exclusive with `branch`.
-    #[serde(default)]
-    pub snapshot: Option<String>,
-}
-
-/// Response for `POST /queries/{name}`: the read envelope for a stored
-/// read, or the mutation envelope for a stored mutation. Serialized
-/// **untagged**, so the wire shape is exactly [`ReadOutput`] or
-/// [`ChangeOutput`] — classification follows the stored query, not a
-/// wrapper field.
-#[derive(Debug, Serialize, ToSchema)]
-#[serde(untagged)]
-pub enum InvokeStoredQueryResponse {
-    Read(ReadOutput),
-    Change(ChangeOutput),
-}
-
-/// The kind of a stored-query parameter, decomposed so a client (e.g. an
-/// MCP server) can build a typed input schema with a closed `match` and
-/// never re-parse omnigraph's type spelling. `bigint`/`date`/`datetime`/
-/// `blob` are carried as JSON strings on the wire: a 64-bit integer past
-/// 2^53 loses precision as a JSON number, and Date/DateTime are ISO
-/// strings, Blob a blob-URI string.
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, ToSchema)]
-#[serde(rename_all = "snake_case")]
-pub enum ParamKind {
-    String,
-    Bool,
-    Int,
-    #[serde(rename = "bigint")]
-    BigInt,
-    Float,
-    Date,
-    #[serde(rename = "datetime")]
-    DateTime,
-    Blob,
-    Vector,
-    List,
-}
-
-/// One declared parameter of a stored query, projected for the catalog.
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct ParamDescriptor {
-    pub name: String,
-    pub kind: ParamKind,
-    /// Element kind when `kind == list` (always a scalar — the grammar
-    /// forbids lists of vectors or nested lists).
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub item_kind: Option<ParamKind>,
-    /// Dimension when `kind == vector`.
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub vector_dim: Option<u32>,
-    /// `false` → the caller must supply it; `true` → optional.
-    pub nullable: bool,
-}
-
-/// One entry in the stored-query catalog (`GET /queries`).
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct QueryCatalogEntry {
-    /// Registry key / invoke path segment (`POST /queries/{name}`).
-    pub name: String,
-    /// MCP tool id (the `tool_name` override, else `name`).
-    pub tool_name: String,
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub description: Option<String>,
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub instruction: Option<String>,
-    /// `true` for a stored mutation → an MCP read-only hint of `false`.
-    pub mutation: bool,
-    pub params: Vec<ParamDescriptor>,
-}
-
-/// Response for `GET /queries`: the `mcp.expose` subset of a graph's
-/// stored-query registry, each with typed parameters.
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct QueriesCatalogOutput {
-    pub queries: Vec<QueryCatalogEntry>,
-}
-
-/// Total map from a resolved scalar to its catalog kind. Exhaustive on
-/// purpose: a new `ScalarType` is a compile error here until catalogued.
-fn scalar_kind(scalar: ScalarType) -> ParamKind {
-    match scalar {
-        ScalarType::String => ParamKind::String,
-        ScalarType::Bool => ParamKind::Bool,
-        ScalarType::I32 | ScalarType::U32 => ParamKind::Int,
-        ScalarType::I64 | ScalarType::U64 => ParamKind::BigInt,
-        ScalarType::F32 | ScalarType::F64 => ParamKind::Float,
-        ScalarType::Date => ParamKind::Date,
-        ScalarType::DateTime => ParamKind::DateTime,
-        ScalarType::Blob => ParamKind::Blob,
-        ScalarType::Vector(_) => ParamKind::Vector,
-    }
-}
-
-fn param_descriptor(param: &Param) -> ParamDescriptor {
-    match PropType::from_param_type_name(&param.type_name, param.nullable) {
-        Some(pt) if pt.list => ParamDescriptor {
-            name: param.name.clone(),
-            kind: ParamKind::List,
-            item_kind: Some(scalar_kind(pt.scalar)),
-            vector_dim: None,
-            nullable: param.nullable,
-        },
-        Some(pt) => {
-            let (kind, vector_dim) = match pt.scalar {
-                ScalarType::Vector(dim) => (ParamKind::Vector, Some(dim)),
-                other => (scalar_kind(other), None),
-            };
-            ParamDescriptor {
-                name: param.name.clone(),
-                kind,
-                item_kind: None,
-                vector_dim,
-                nullable: param.nullable,
-            }
-        }
-        // Unreachable for a parsed query (every declared param type is
-        // grammatical); fall back to an opaque string so the field is still
-        // usable rather than dropped.
-        None => ParamDescriptor {
-            name: param.name.clone(),
-            kind: ParamKind::String,
-            item_kind: None,
-            vector_dim: None,
-            nullable: param.nullable,
-        },
-    }
-}
 
 /// Project a loaded stored query into its catalog entry (typed params,
 /// MCP tool name, read/mutate flag, description/instruction).
@@ -460,246 +22,3 @@ pub fn query_catalog_entry(query: &StoredQuery) -> QueryCatalogEntry {
         params: query.decl.params.iter().map(param_descriptor).collect(),
     }
 }
-
-#[derive(Debug, Clone, Default, Serialize, Deserialize, ToSchema)]
-pub struct SchemaApplyRequest {
-    /// Project schema in `.pg` source form. The diff against the current
-    /// schema produces the migration steps that will be applied.
-    #[schema(
-        example = "node Person {\n    name: String @key\n    age: I32?\n}\n\nedge Knows: Person -> Person"
-    )]
-    pub schema_source: String,
-    /// When true, promote every `DropMode::Soft` step in the plan to
-    /// `DropMode::Hard`, making the prior column data unreachable
-    /// after the apply. Matches the CLI's `--allow-data-loss` flag.
-    /// Defaults to `false` (drops remain reversible via time travel).
-    #[serde(default)]
-    pub allow_data_loss: bool,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct SchemaApplyOutput {
-    pub uri: String,
-    pub supported: bool,
-    pub applied: bool,
-    pub step_count: usize,
-    pub manifest_version: u64,
-    #[schema(value_type = Vec<Value>)]
-    pub steps: Vec<SchemaMigrationStep>,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct SchemaOutput {
-    pub schema_source: String,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct IngestRequest {
-    /// Target branch. Defaults to `main`. Without `from`, the branch must
-    /// already exist — a missing branch is a 404, never an implicit fork.
-    pub branch: Option<String>,
-    /// Parent branch used to create `branch` if it does not exist. Branch
-    /// creation is opt-in by presence of this field; omit it to require an
-    /// existing branch.
-    pub from: Option<String>,
-    /// How existing rows are handled. Defaults to `merge`.
-    #[schema(value_type = Option<LoadModeSchema>)]
-    pub mode: Option<LoadMode>,
-    /// NDJSON payload: one record per line, each shaped
-    /// `{"type": "<TypeName>", "data": {...}}`.
-    #[schema(
-        example = "{\"type\": \"Person\", \"data\": {\"name\": \"Alice\", \"age\": 30}}\n{\"type\": \"Person\", \"data\": {\"name\": \"Bob\", \"age\": 25}}"
-    )]
-    pub data: String,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct ExportRequest {
-    /// Branch to export. Defaults to `main`.
-    pub branch: Option<String>,
-    /// Restrict the export to these node/edge type names. Empty exports all types.
-    #[serde(default)]
-    pub type_names: Vec<String>,
-    /// Restrict the export to these table keys. Empty exports all tables.
-    #[serde(default)]
-    pub table_keys: Vec<String>,
-}
-
-#[derive(Debug, Clone, Deserialize, IntoParams)]
-pub struct SnapshotQuery {
-    pub branch: Option<String>,
-}
-
-#[derive(Debug, Clone, Deserialize, IntoParams)]
-pub struct CommitListQuery {
-    pub branch: Option<String>,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct HealthOutput {
-    pub status: String,
-    pub version: String,
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub source_version: Option<String>,
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, ToSchema)]
-#[serde(rename_all = "snake_case")]
-pub enum ErrorCode {
-    Unauthorized,
-    Forbidden,
-    BadRequest,
-    NotFound,
-    /// 405 Method Not Allowed — the route exists but the active server
-    /// mode doesn't serve this method (e.g. `GET /graphs` in single-graph
-    /// mode). Distinct from 404 so clients can tell "wrong context" from
-    /// "no such resource."
-    MethodNotAllowed,
-    Conflict,
-    /// 429 Too Many Requests — per-actor admission cap exceeded.
-    /// Clients should respect the `Retry-After` header.
-    TooManyRequests,
-    Internal,
-}
-
-/// Structured details for a publisher-level OCC failure. Surfaces alongside
-/// HTTP 409 when a write was rejected because the caller's pre-write view of
-/// one table's manifest version was stale relative to the current head. The
-/// expected/actual fields tell the client which table to refresh.
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct ManifestConflictOutput {
-    pub table_key: String,
-    pub expected: u64,
-    pub actual: u64,
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct ErrorOutput {
-    pub error: String,
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub code: Option<ErrorCode>,
-    #[serde(default, skip_serializing_if = "Vec::is_empty")]
-    pub merge_conflicts: Vec<MergeConflictOutput>,
-    /// Set when the conflict is a publisher CAS rejection
-    /// (`ManifestConflictDetails::ExpectedVersionMismatch`). The caller's
-    /// pre-write view of `table_key` was at version `expected` but the
-    /// manifest is now at `actual`. Refresh and retry.
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub manifest_conflict: Option<ManifestConflictOutput>,
-}
-
-pub fn snapshot_payload(branch: &str, snapshot: &Snapshot) -> SnapshotOutput {
-    let mut entries: Vec<_> = snapshot.entries().cloned().collect();
-    entries.sort_by(|a, b| a.table_key.cmp(&b.table_key));
-    let tables = entries
-        .iter()
-        .map(|entry| SnapshotTableOutput {
-            table_key: entry.table_key.clone(),
-            table_path: entry.table_path.clone(),
-            table_version: entry.table_version,
-            table_branch: entry.table_branch.clone(),
-            row_count: entry.row_count,
-        })
-        .collect::<Vec<_>>();
-    SnapshotOutput {
-        branch: branch.to_string(),
-        manifest_version: snapshot.version(),
-        tables,
-    }
-}
-
-pub fn schema_apply_output(uri: &str, result: SchemaApplyResult) -> SchemaApplyOutput {
-    SchemaApplyOutput {
-        uri: uri.to_string(),
-        supported: result.supported,
-        applied: result.applied,
-        step_count: result.steps.len(),
-        manifest_version: result.manifest_version,
-        steps: result.steps,
-    }
-}
-
-pub fn commit_output(commit: &GraphCommit) -> CommitOutput {
-    CommitOutput {
-        graph_commit_id: commit.graph_commit_id.clone(),
-        manifest_branch: commit.manifest_branch.clone(),
-        manifest_version: commit.manifest_version,
-        parent_commit_id: commit.parent_commit_id.clone(),
-        merged_parent_commit_id: commit.merged_parent_commit_id.clone(),
-        actor_id: commit.actor_id.clone(),
-        created_at: commit.created_at,
-    }
-}
-
-pub fn read_output(query_name: String, target: &ReadTarget, result: QueryResult) -> ReadOutput {
-    let columns = result
-        .schema()
-        .fields()
-        .iter()
-        .map(|field| field.name().clone())
-        .collect();
-    ReadOutput {
-        query_name,
-        target: read_target_output(target),
-        row_count: result.num_rows(),
-        columns,
-        rows: result.to_rust_json(),
-    }
-}
-
-pub fn ingest_output(
-    uri: &str,
-    result: &LoadResult,
-    mode: LoadMode,
-    actor_id: Option<String>,
-) -> IngestOutput {
-    IngestOutput {
-        uri: uri.to_string(),
-        branch: result.branch.clone(),
-        base_branch: result.base_branch.clone(),
-        branch_created: result.branch_created,
-        mode,
-        tables: result
-            .to_ingest_tables()
-            .into_iter()
-            .map(|table| IngestTableOutput {
-                table_key: table.table_key,
-                rows_loaded: table.rows_loaded,
-            })
-            .collect(),
-        actor_id,
-    }
-}
-
-pub fn read_target_output(target: &ReadTarget) -> ReadTargetOutput {
-    match target {
-        ReadTarget::Branch(branch) => ReadTargetOutput {
-            branch: Some(branch.clone()),
-            snapshot: None,
-        },
-        ReadTarget::Snapshot(snapshot) => ReadTargetOutput {
-            branch: None,
-            snapshot: Some(snapshot.as_str().to_string()),
-        },
-    }
-}
-
-// ─── MR-668 — management endpoint shapes ──────────────────────────────────
-
-/// One entry in the response from `GET /graphs`. Cluster operators
-/// consume this list to discover which graphs the server is currently
-/// serving. The shape is intentionally minimal — `graph_id` and `uri`
-/// are the only fields a routing client needs.
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct GraphInfo {
-    pub graph_id: String,
-    pub uri: String,
-}
-
-/// Response from `GET /graphs`. Lists every graph registered with the
-/// server in alphabetical order by `graph_id` (sorted server-side so
-/// clients get deterministic output across requests).
-#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
-pub struct GraphListResponse {
-    pub graphs: Vec<GraphInfo>,
-}