Ref Tools MCP
MCP server that gives coding agents token-efficient access to public and private API/library documentation, filtering results to the most relevant ~5k tokens per query and deduplicating searches within sessions to prevent context rot.
Score Breakdown
⚙ Agent Friendliness
🔒 Security
Reference/documentation tools MCP. Read-only access to documentation sources. Low security risk. Validate source URLs to prevent SSRF attacks.
⚡ Reliability
Best When
You have coding agents that frequently look up API and library documentation and are experiencing context bloat or degraded model performance from irrelevant documentation chunks.
Avoid When
Your agents work with a fixed, small set of well-known libraries already in the model's training data, or you need fully offline documentation access.
Use Cases
- • Give coding agents access to third-party API documentation without bloating context with irrelevant pages
- • Search private library or internal documentation not indexed by default in LLM training data
- • Reduce LLM API costs by eliminating unnecessary documentation tokens during agentic coding loops
- • Provide a web URL reader that converts pages to clean markdown for agent consumption
- • Keep agent sessions on track by filtering previously seen search results within a session
Not For
- • General web browsing or non-documentation content retrieval
- • Offline or air-gapped environments (requires API key and internet access)
- • Teams who need self-hosted documentation indexing without a SaaS dependency
Interface
Authentication
API key required, passed as query parameter (streamable HTTP) or environment variable REF_API_KEY (stdio). Key obtained via signup at ref.tools.
Pricing
Requires signup for API key; specific pricing tiers not detailed in README. Free tier availability implied by signup model.
Agent Metadata
Known Gotchas
- ⚠ API key in URL query parameter (streamable HTTP mode) may appear in server logs — prefer stdio mode for sensitive environments
- ⚠ Session-scoped deduplication means restarting the MCP session resets search history, which may cause redundant lookups across agent restarts
- ⚠ Private library support requires documentation to be indexed by ref.tools — indexing process and SLA not documented
- ⚠ Only 2 tools (ref_search_documentation, ref_read_url) — intentionally minimal but may require multiple calls for complex lookups
Alternatives
Full Evaluation Report
Detailed scoring breakdown, competitive positioning, security analysis, and improvement recommendations for Ref Tools MCP.
Scores are editorial opinions as of 2026-03-06.