dograh/api/tests/test_mcp_docs_search.py
Leoy 5762095edf
feat(mcp): add search_docs tool over docs corpus (closes #295) (#316)
* feat(mcp): add search_docs tool over Mintlify docs corpus

Closes #295. The docs at https://docs.dograh.com promise "Search the
Dograh docs for how to configure a TURN server" as an MCP example
prompt, but no search_docs tool exists in the MCP server — agents can
list workspace resources but cannot search the documentation.

This adds a dependency-free, in-process keyword search over the
`docs/` tree shipped into the API image (`COPY ./docs ./docs`):

- New `api/mcp_server/tools/docs_search.py` — async `search_docs(query,
  limit=10)` with weighted scoring (path > title > body), a 25-result
  hard cap, snippet extraction around the first term hit, and graceful
  empty-list degradation when docs aren't on disk. `DOGRAH_DOCS_PATH`
  env var overrides location discovery for non-Docker layouts.

- Registered in `api/mcp_server/server.py` alongside the other tools,
  keeping the existing list-alphabetical convention.

- `api/tests/test_mcp_docs_search.py` — 18 unit tests covering the
  pure helpers (tokenizer, frontmatter stripping, title extraction,
  scoring weights, URL building) and end-to-end ranking, limit
  clamping, empty-corpus degradation, and input-validation errors.
  Mocks `authenticate_mcp_request` to avoid the DB dependency,
  mirroring `test_mcp_save_workflow.py`.

Implementation notes:
- The docs corpus is ~100 files / ~140k LoC, so a per-call scan runs
  well under 50 ms; avoiding a vector index / embedding backend keeps
  the tool zero-dependency and works for fully offline self-hosted
  deployments.
- Authentication is required for consistency with the other MCP tools
  (and to route through the existing rate-limit middleware), even
  though docs are not org-scoped data.
- Title/path matches deliberately outweigh body matches so a page
  whose subject IS the query term outranks one that merely mentions
  it incidentally.

* feat: improve docs search

---------

Co-authored-by: Abhishek Kumar <abhishek@a6k.me>
2026-05-20 18:20:35 +05:30

359 lines
11 KiB
Python

"""Unit tests for the MCP docs discovery tools."""
from __future__ import annotations
import os
from pathlib import Path
from unittest.mock import AsyncMock, patch
import pytest
from fastapi import HTTPException
from api.mcp_server.tools import docs_search as docs_search_module
from api.mcp_server.tools.docs_search import (
_docs_index,
_extract_page_title,
_resolve_docs_root,
_score_page,
_strip_frontmatter,
_tokenize_query,
list_docs,
read_doc,
search_docs,
)
def _clear_docs_caches() -> None:
docs_search_module._docs_index.cache_clear()
@pytest.fixture
def fake_docs_root(tmp_path: Path) -> Path:
docs_root = tmp_path / "docs"
docs_root.mkdir()
(docs_root / "getting-started").mkdir()
(docs_root / "getting-started" / "index.mdx").write_text(
"---\n"
'title: "Getting started"\n'
'description: "Start using Dograh."\n'
"---\n\n"
"# Getting started\n\n"
"Welcome to Dograh.\n",
encoding="utf-8",
)
(docs_root / "voice-agent").mkdir()
(docs_root / "voice-agent" / "introduction.mdx").write_text(
"---\n"
'title: "Voice Agent Builder"\n'
'description: "Build conversational workflows."\n'
"---\n\n"
"# Voice Agent Builder\n\n"
"Build workflows with nodes and tools.\n",
encoding="utf-8",
)
(docs_root / "voice-agent" / "tools").mkdir()
(docs_root / "voice-agent" / "tools" / "mcp-tool.mdx").write_text(
"---\n"
'title: "MCP Tool"\n'
'description: "Connect external MCP servers."\n'
'llm_hint: "Use for MCP server setup, remote tools, or model context protocol questions."\n'
"aliases:\n"
' - "model context protocol"\n'
"---\n\n"
"# MCP Tool\n\n"
"Connect an external MCP server to your voice agent.\n\n"
"## Authentication\n\n"
"Provide the MCP endpoint URL and headers.\n",
encoding="utf-8",
)
(docs_root / "deployment").mkdir()
(docs_root / "deployment" / "docker.mdx").write_text(
"---\n"
'title: "Docker"\n'
'description: "Deploy Dograh with Docker."\n'
'llm_hint: "Use for Docker deployment, local setup, remote setup, TURN server, coturn, or WebRTC connectivity questions."\n'
"aliases:\n"
' - "coturn"\n'
' - "turn server"\n'
"---\n\n"
"# Docker\n\n"
"Run Dograh with Docker.\n\n"
"## Troubleshooting WebRTC Connectivity\n\n"
"If audio fails or ICE fails, configure a TURN server. Coturn is the recommended choice.\n",
encoding="utf-8",
)
# Hidden/orphaned docs page: present on disk but not in docs.json, so it
# must not be indexed by the MCP tools.
(docs_root / "internal-only.mdx").write_text(
"---\n"
'title: "Internal TURN Notes"\n'
"---\n\n"
"# Internal TURN Notes\n\n"
"This page mentions zyxinternalturntoken but is not user-facing.\n",
encoding="utf-8",
)
(docs_root / "AGENTS.md").write_text("# Internal instructions\n", encoding="utf-8")
(docs_root / "docs.json").write_text(
"""{
"navigation": {
"tabs": [
{
"tab": "Guides",
"groups": [
{
"group": "Getting started",
"pages": [
"getting-started/index"
]
},
{
"group": "Voice Agent Builder",
"pages": [
"voice-agent/introduction",
{
"group": "Tools",
"pages": [
"voice-agent/tools/mcp-tool"
]
}
]
}
]
},
{
"tab": "Developer",
"groups": [
{
"group": "Deployment",
"pages": [
"deployment/docker"
]
}
]
}
]
}
}
""",
encoding="utf-8",
)
_clear_docs_caches()
with patch.dict(os.environ, {"DOGRAH_DOCS_PATH": str(docs_root)}):
yield docs_root
_clear_docs_caches()
@pytest.fixture
def authed_user():
class _FakeUser:
selected_organization_id = 1
id = 42
with patch(
"api.mcp_server.tools.docs_search.authenticate_mcp_request",
new=AsyncMock(return_value=_FakeUser()),
):
yield _FakeUser()
def test_tokenize_query_dedupes_and_drops_stopwords():
assert _tokenize_query("How do I configure a TURN server TURN?") == [
"configure",
"turn",
"server",
]
def test_tokenize_query_empty_input_returns_empty():
assert _tokenize_query("") == []
assert _tokenize_query("?? // !!") == []
def test_strip_frontmatter_removes_yaml_block():
body = '---\ntitle: "X"\n---\n\n# Heading\n'
assert _strip_frontmatter(body).startswith("# Heading")
def test_extract_page_title_prefers_frontmatter():
body = '---\ntitle: "Front Title"\n---\n\n# Heading Title\n'
assert _extract_page_title(body, fallback="x.mdx") == "Front Title"
def test_extract_page_title_falls_back_to_first_heading():
body = "# Heading Title\nbody\n"
assert _extract_page_title(body, fallback="x.mdx") == "Heading Title"
def test_score_page_uses_llm_hint_and_aliases():
page = docs_search_module.DocPage(
path="deployment/docker",
file_path="deployment/docker.mdx",
title="Docker",
description="Deploy Dograh with Docker.",
llm_hint="Use for TURN server and coturn setup.",
aliases=("coturn",),
breadcrumb=("Developer", "Deployment"),
content="Docker deployment.",
sections=(
docs_search_module.DocSection(
title="Troubleshooting WebRTC Connectivity",
slug="troubleshooting-webrtc-connectivity",
level=2,
content="Configure a TURN server with coturn.",
),
),
order=0,
)
score, section = _score_page(page, ["coturn"])
assert score > 0
assert section is not None
assert section.slug == "troubleshooting-webrtc-connectivity"
def test_resolve_docs_root_honors_env_override(tmp_path: Path):
docs = tmp_path / "custom_docs"
docs.mkdir()
(docs / "docs.json").write_text("{}", encoding="utf-8")
with patch.dict(os.environ, {"DOGRAH_DOCS_PATH": str(docs)}):
assert _resolve_docs_root() == docs.resolve()
@pytest.mark.asyncio
async def test_search_docs_ranks_turn_doc_and_uses_route_path(
fake_docs_root, authed_user
):
results = await search_docs("How do I configure coturn for WebRTC?")
assert results
assert results[0]["path"] == "deployment/docker"
assert results[0]["section_slug"] == "troubleshooting-webrtc-connectivity"
assert "TURN server" in results[0]["llm_hint"]
assert "snippet" not in results[0]
assert "score" not in results[0]
assert "url" not in results[0]
@pytest.mark.asyncio
async def test_search_docs_indexes_only_docs_json_pages(fake_docs_root, authed_user):
results = await search_docs("zyxinternalturntoken")
assert results == []
@pytest.mark.asyncio
async def test_search_docs_respects_limit(fake_docs_root, authed_user):
results = await search_docs("dograh", limit=1)
assert len(results) == 1
@pytest.mark.asyncio
async def test_search_docs_returns_empty_when_no_match(fake_docs_root, authed_user):
assert await search_docs("xyzzy unrelated zzz") == []
@pytest.mark.asyncio
async def test_search_docs_returns_empty_when_no_corpus(
tmp_path, authed_user, monkeypatch
):
nonexistent = tmp_path / "no-docs-here"
monkeypatch.setenv("DOGRAH_DOCS_PATH", str(nonexistent))
_clear_docs_caches()
with patch(
"api.mcp_server.tools.docs_search._resolve_docs_root", return_value=None
):
assert await search_docs("anything") == []
@pytest.mark.asyncio
async def test_search_docs_rejects_empty_query(fake_docs_root, authed_user):
with pytest.raises(ValueError, match="non-empty string"):
await search_docs("")
@pytest.mark.asyncio
async def test_search_docs_rejects_query_with_only_stopwords(
fake_docs_root, authed_user
):
with pytest.raises(ValueError, match="non-stopword"):
await search_docs("how do I")
@pytest.mark.asyncio
async def test_search_docs_rejects_zero_limit(fake_docs_root, authed_user):
with pytest.raises(ValueError, match="at least 1"):
await search_docs("Dograh", limit=0)
@pytest.mark.asyncio
async def test_list_docs_returns_top_level_sections(fake_docs_root, authed_user):
results = await list_docs()
assert results[0]["kind"] == "section"
assert results[0]["path"] == "guides/getting-started"
assert results[1]["path"] == "guides/voice-agent-builder"
@pytest.mark.asyncio
async def test_list_docs_depth_expands_children(fake_docs_root, authed_user):
results = await list_docs("guides/voice-agent-builder", depth=2)
paths = [item["path"] for item in results]
assert "voice-agent/introduction" in paths
assert "guides/voice-agent-builder/tools" in paths
assert "voice-agent/tools/mcp-tool" in paths
@pytest.mark.asyncio
async def test_list_docs_rejects_unknown_section(fake_docs_root, authed_user):
with pytest.raises(HTTPException, match="Unknown docs section"):
await list_docs("nope")
@pytest.mark.asyncio
async def test_read_doc_returns_full_page_and_sections(fake_docs_root, authed_user):
result = await read_doc("deployment/docker")
assert result["path"] == "deployment/docker"
assert result["title"] == "Docker"
assert "url" not in result
section_slugs = [section["slug"] for section in result["sections"]]
assert "docker" in section_slugs
assert "troubleshooting-webrtc-connectivity" in section_slugs
assert "Coturn" in result["content"] or "coturn" in result["content"].lower()
@pytest.mark.asyncio
async def test_read_doc_can_target_section(fake_docs_root, authed_user):
result = await read_doc(
"deployment/docker",
section="troubleshooting-webrtc-connectivity",
)
assert result["section_slug"] == "troubleshooting-webrtc-connectivity"
assert "ICE fails" in result["content"] or "TURN server" in result["content"]
assert "Run Dograh with Docker." not in result["content"]
@pytest.mark.asyncio
async def test_read_doc_rejects_unknown_page(fake_docs_root, authed_user):
with pytest.raises(HTTPException, match="Unknown docs page"):
await read_doc("missing/page")
@pytest.mark.asyncio
async def test_read_doc_rejects_unknown_section(fake_docs_root, authed_user):
with pytest.raises(HTTPException, match="Unknown section"):
await read_doc("deployment/docker", section="missing-section")
def test_docs_index_uses_docs_json_navigation(fake_docs_root):
index = _docs_index()
assert "internal-only" not in index.pages_by_path
assert "guides/voice-agent-builder/tools" in index.sections_by_path
assert index.pages_by_path["voice-agent/tools/mcp-tool"].breadcrumb == (
"Guides",
"Voice Agent Builder",
"Tools",
)