Luc Lauzon a8550410b0 feat(mcp): add per-tool _meta["anthropic/maxResultSizeChars"] annotation (#56) ... Claude Code v2.1.91+ honors the per-tool annotation `_meta["anthropic/maxResultSizeChars"]` (up to 500_000) to override its 50K default truncation of `CallToolResult`. Without it, large Vestige payloads are silently truncated and spilled to disk, forcing the parent agent to chunk-read them. Empirically observed truncation under realistic default parameters (measured on v1.3.0 against ~3,300 memories; v2.x tool surface preserves the same names + payload shapes): search(detail_level="full", limit=20) -> 134,824 chars -> truncated search(detail_level="summary", limit=10) -> 71,318 chars -> truncated memory_timeline(limit=30) -> 83,626 chars -> truncated This patch: 1. Adds `meta: Option<serde_json::Value>` to `ToolDescription` with `#[serde(rename = "_meta")]` so the wire shape matches the MCP spec. Backwards-compatible (the field is optional + `skip_serializing_if`; older MCP clients ignore unknown JSON keys per the spec). 2. Derives `Default` on `ToolDescription` so existing call sites can adopt the new field via struct-update syntax (`..Default::default()`) without restating it. 3. Annotates the four high-payload tools per measurement-driven discipline; the other 21 tools deliberately do NOT carry the annotation (cargo-cult prevention — a generous cap on every tool dilutes the signal and trains future maintainers that the value is arbitrary): - search -> 300_000 (2.2x headroom over observed peak) - memory_timeline -> 200_000 (2.4x headroom over observed peak) - memory -> 100_000 (single-record bounded) - codebase -> 100_000 (future-growth bounded) Tools that COULD plausibly grow into the annotated set with future workload (`deep_reference`, `cross_reference`, `memory_graph`, `explore_connections`, `session_context`) are left unannotated until empirical measurement shows truncation under realistic use. 4. Adds three regression tests in `server::tests`: - test_high_payload_tools_have_max_result_size_annotation: pins each cap value + asserts <= 500K Anthropic ceiling - test_other_tools_do_not_carry_max_result_size_annotation: cargo-cult prevention; dynamically iterates `tools/list` and asserts every tool NOT in the discipline-prescribed set lacks the annotation (robust to new tools being added by future PRs) - test_meta_wire_shape_uses_underscore_meta_field: pins the serde rename to `_meta` (the spec'd wire name) so a refactor of `ToolDescription` cannot silently drop the rename All 22 `server::tests` pass on v2.1.22 base (19 pre-existing + 3 new). Full lib test suite: 379/380 pass; the 1 unrelated failure (`tools::maintenance::tests::test_portable_export_writes_archive_to_storage_exports_dir`) is a pre-existing Windows path-separator assertion bug in `tools/maintenance.rs:823` (`path.ends_with("exports/portable-test.json")` fails on Windows where the path uses `\`) — unaffected by this PR. References: - Anthropic CC v2.1.91 release notes (April 2026): "Added MCP tool result persistence override via _meta['anthropic/maxResultSizeChars'] annotation (up to 500K), allowing larger results like DB schemas to pass through without truncation" - claude-agent-sdk-python v0.1.55 #756: forward bookkeeping establishing the on-Tool-definition (not on-CallToolResult) semantics for this annotation Co-authored-by: Peter Lauzon <inbijiburu@protonmail.com>		2026-05-25 13:49:51 -05:00
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vestige-core	Release v2.1.22 Sanhedrin receipts (#55)	2026-05-25 01:44:52 -05:00
vestige-mcp	feat(mcp): add per-tool _meta["anthropic/maxResultSizeChars"] annotation (#56)	2026-05-25 13:49:51 -05:00