patentref-mcp

The only free API and MCP tool we know of that returns a US patent's claim tree with element segmentation, antecedent links and character offsets, built by deterministic code, 1976 to now.

patentref-mcp is an MCP server for the PatentRef API (https://patentref.io). Each tool sends one HTTPS request to the public API with the key from its environment and returns the API's JSON as the API sent it.

Run

pip install patentref-mcp
export PATENTREF_API_KEY=...        # a key from https://patentref.io/api/v1/meta/signup/
patentref-mcp                       # stdio, what most MCP clients start
patentref-mcp --http --port 8787    # streamable HTTP at http://127.0.0.1:8787/mcp

Claude Desktop (claude_desktop_config.json):

{"mcpServers": {"patentref": {"command": "patentref-mcp", "env": {"PATENTREF_API_KEY": "..."}}}}

Environment: PATENTREF_API_KEY (sent by every tool but build_facts and search_disclosures), PATENTREF_BASE (default https://patentref.io), PATENTREF_TIMEOUT (seconds, default 30).

Check an install: python -m patentref_mcp.smoke 10000364 starts the server over stdio, lists its tools, makes two tool calls and prints the transcript.

Tools

• get_claim_tree(patent_id): one patent's claims as a tree, from the claim text as the USPTO published it; every part carries start and end offsets into its claim's text. GET /api/v1/structure/claims/<patent_id>/
• get_patent_brief(patent_id, max_tokens): one patent in a fixed order, cut to fit max_tokens (300 to 32000, default 2000), each independent claim as its elements with their offsets. GET /api/v1/structure/brief/<patent_id>/
• check_patent_status(patent_id): the status record of one patent, with its basis, as-of date and data version. GET /api/v1/lapse/status/<patent_id>/
• search_patents(q, f, s, size, after): the PatentSearch v1 query grammar. GET /api/v1/patent/
• similar_patents(text, n): the US patents nearest to a title and abstract. GET /api/v1/lapse/similar
• build_facts(): the data version and as-of date in service. GET /api/v1/meta/
• search_disclosures(q): public records of the PatentRef registry. GET /registry/search
• rep_required, fee_schedule, route_windows, pph_routes, ai_use_statement_required, grace_period, rules_changelog, rules_index: rows of patent office rules, each with its source URL and a verbatim quote. GET /api/v1/rules/

An error from the API comes back as the tool's error text: the HTTP status and the API's X-Status-Reason. The server does not retry.

License

MIT, see LICENSE. The data the API returns has its own license and attribution lines: https://patentref.io/LICENSES.md