Crawlgraph MCP

crawlgraph-mcp

Five MCP tools for backlink research using CrawlGraph and Common Crawl snapshots: backlinks, backlink_changes, gap_analysis, gap_outreach_targets, and releases. Outreach tools identify research candidates; they do not send messages or create contacts.

Choose an authentication profile

Legacy /mcp also accepts Smithery's ?apiKey=… and base64 JSON ?config=… forms. Header credentials take precedence, then apiKey, then packed config. Prefer the Authorization header. The connector endpoint rejects API keys, query credentials and packed configuration; OAuth tokens never go to the public /api/v1 API.

Directory approval and real Claude/OpenAI compatibility verification remain pending. No Verified listing or logo is claimed. This checkout's source version is 0.4.0; it does not establish the current npm or hosted version. Verify each distribution separately through the operator runbooks linked in DEPLOY.md.

API-key setup: npm / stdio and legacy HTTP

Obtain a key through CrawlGraph's API onboarding. The free-key flow emails a key; it does not sign you into an account.

For Claude Desktop / Claude Code, put this in your client's MCP configuration:

{

"mcpServers": { "crawlgraph": { "command": "npx", "args": ["-y", "crawlgraph-mcp"], "env": { "CRAWLGRAPH_API_KEY": "cg_live_your_key_here" } } } }

Cursor, Windsurf, Cline and Zed use the same command/environment arrangement. Streamable HTTP clients can use https://crawlgraph.com/mcp with their own bearer API key. Confirm the hosted tools/list response before relying on a specific source feature.

Account linking: OAuth connector

When the operator enables the reviewed service, connect to https://crawlgraph.com/mcp/connectors using an existing CrawlGraph account, sign in and approve consent in the original connection browser. Account creation is outside OAuth. If you need an account, follow the disclosed onboarding flow, then return and request sign-in; an emailed API key alone is not a login session.

The issuer is https://crawlgraph.com, the exact resource is https://crawlgraph.com/mcp/connectors, and the only scope is crawlgraph:read. Public clients use authorization code plus S256 PKCE and token_endpoint_auth_method=none. Omitted registration auth method is normalized to none and any SDK-generated secret is discarded. Confidential client methods and metadata-document fetching are unsupported. Callbacks must be exact operator-approved HTTPS URLs. OpenAI's callback must come from the actual portal; this repository does not supply a guessed callback.

Authorization and code exchange require the exact raw resource value. At code exchange a supplied redirect_uri must exactly match the stored callback; omission retains that callback. Refresh may omit resource and scope to retain the original grant. PKCE is validated by the backend during the atomic code exchange, alongside client/resource/redirect/scope checks.

Use account connection management to disconnect and revoke the entire grant and refresh family. An expired access token can be refreshed while its grant and refresh family remain valid; revoked or expired grants require reconnecting. Discovery, OAuth and introspection outages return 503 without a relink challenge. Execution outages return a safe tool error inside the HTTP 200 MCP result, without relink metadata. Tool-time revocation is reported through mcp/www_authenticate result metadata. Refresh rotation has no retry grace: concurrent reuse revokes the family, and a lost token response may require reconnecting. A 503 after a possible commit does not promise an unused code or refresh token.

Quotas and directory tools

Both auth profiles share the account's UTC calendar-month counters. Free accounts have 15 backlinks calls and 0 gap jobs; accounts with current paid access have 1,000 backlinks calls and 50 gap jobs. Paid eligibility follows the backend's current entitlement rules. Release inventory consumes no research quota. backlink_changes shares the backlinks counter.

Directory inputs and costs:

Directory lists default to 20, maximum 100. The complete serialized UTF-8 CallToolResult, including structured data, text and metadata, is limited to 65,536 bytes. Additional output clipping is disclosed in crawlgraph/output metadata, retaining original observed totals, source caps, quota accounting, provenance and job handles. Large exports belong on the account/API surface.

Gap tools poll for at most 75 seconds within a 90-second tool budget. A pending result includes job_id and the normalized request. Resume the same tool with that handle and query; a fresh valid grant for the same owner can resume after reconnecting. Polling costs zero gap jobs. Never automatically submit a replacement after timeout, cancellation, network loss or a stale worker: the accepted job may still complete. Cancellation stops further polling. An accepted submission remains charged; a lost/malformed response reports unknown consumption rather than claiming zero.

Node writes bounded JSON telemetry to stderr. Each directory tool call records an internally generated correlation ID, fixed tool name (or unknown), final envelope status, isError, allowlisted primary and partial error codes, latency, and the exact final serialized UTF-8 result size, excluding transport framing. Known charged-call counts and unknown-consumption categories come from the final envelope. Pending cancellations and completed results with partial revocation retain their distinct status and error fields. HTTP/OAuth errors record only a fixed route category, status, allowlisted code and a separate response-local correlation ID. Logging failures cannot change responses. Logs omit arguments, domains, results, job/account/grant/client/source IDs, caller request IDs, exception text, URLs, headers, configuration and credentials.

OAuth source admission groups IPv6 addresses by /64 only in the local bucket key; mapped IPv4 addresses use the same bucket as their IPv4 form. Private RPCs still receive the full normalized verified ingress source. The bounded bucket map fails closed at capacity without evicting live windows; the backend continues enforcing its own policies.

Outreach preserves the backend ranking by competitor overlap, authority and domain. Platform-filter counts describe only the returned backend sample. Enrichment defaults to 0; explicitly request enrich_authority_top=N (0–5) for up to N extra backlinks calls on retained targets. Partial failures retain completed results, per-item provenance, actual known charges, the latest observed quota and any unknown consumption. Verified jobs use their attested release for enrichment; legacy jobs keep null provenance and record separate lookup releases.

Legacy tools retain their original fields and defaults: backlinks defaults to 1,000 rows at the public API, maximum 10,000; outreach uses enrich_top, default 10, maximum 25, with one backlinks call per enrichment. Legacy gap tools submit and poll within their existing 90-second window and have no directory job_id input. Check the selected profile before estimating quota use.

Interpret results

Common Crawl is a periodic observation, not live link monitoring. Named release provenance does not prove that a page currently links to a target. A removed referring domain means it was not observed in the newer snapshot, not proven live deletion. Unavailable comparison differs from zero changes; unknown totals and source-capped lower bounds differ from complete empty results. Gap provenance is saved at execution and retained on later polling. Older unattested artifacts report legacy_unverified and null release identity. A referring-domain overlap suggests a research candidate, not that a publisher has never heard of you.

Example research prompt:

Find backlink gaps for mine.example against a.example and b.example. If

pending, resume the returned job without resubmitting. Report provenance,

caps and quota use before proposing any optional authority enrichment.

Develop and validate

npm install

npm run build node --test tests/*.test.mjs

The build is also the TypeScript check; no separate lint script is configured. Tests use the installed SDK, local HTTP fixtures and fake private/public backend replies. They require permission to bind loopback sockets and never need production credentials or live provider access. Node fixtures do not prove the backend's SQLite transactions, quota isolation or query pinning; separate crawlback backend HTTP tests and the full release gates cover those.

Implementation references: HTTP surfaces, OAuth router, provider, private backend client, directory tools, and legacy server.

License

MIT