Compare: JustClaw-It vs Context7, Exa and Ref
Context7, Exa and Ref are MCP servers that give coding agents context from the web: library documentation, web pages or code examples. JustClaw-It gives your agent something different: whole, reusable source files mined from open-source repositories, each with its licence and attribution. This page sets out what each one returns, using only facts from each project's own public repository.
Checked on 1 November 2026 against the projects' GitHub repositories (linked under each product). We could not check the vendors' websites for this page, so it states no prices for them. See their pricing pages, and check anything important yourself: these projects change often.
At a glance
| JustClaw-It | Context7 | Exa | Ref | |
|---|---|---|---|---|
| What you get back | full source of a component, with an attribution header | documentation and code examples for a library | web search results and fetched pages | documentation search results and page excerpts |
| Where it comes from | 1,573,603 components mined from open-source repositories | library documentation (projects are listed and submitted to Context7) | the web, through Exa's search | public docs on the web or GitHub, plus your own private repos and PDFs |
| Main MCP tools | search_components, get_component | resolve-library-id, query-docs | web_search_exa, web_fetch_exa | ref_search_documentation, ref_read_url |
| SPDX licence on each result | yes | not mentioned | not mentioned | not mentioned |
| Quality score per result | yes, 0-10 with five sub-scores | not mentioned | not mentioned | not mentioned |
| API key | not needed for search (small per-network limit); free key for pulls | optional, for higher rate limits | optional, for higher rate limits | required |
| Its own MCP server code | not open source | MIT | MIT | MIT |
"Not mentioned" means the project's repository doesn't describe it, not that we proved it is absent.
Context7
Context7, by Upstash, provides "up-to-date, version-specific documentation and code examples" for libraries. Its MCP server has two tools: resolve-library-id turns a library name into a Context7 id, and query-docs fetches documentation and examples for a question, with an optional language to rank examples in that language first. You connect to the remote server at https://mcp.context7.com/mcp; an API key is optional and raises the rate limits. The MCP server is MIT-licensed, while its API backend, parsing engine and crawling engine are private. The project notes that listed projects are maintained by their owners, and that it "cannot guarantee the accuracy, completeness, or security of all library documentation".
Source: github.com/upstash/context7. Pricing: context7.com.
Exa
Exa is a web search API. Its MCP server enables web_search_exa (search results with cleaned page content) and web_fetch_exa (a full page as Markdown) by default; more tools can be switched on. The older code tool, get_code_context_exa, is marked deprecated in the source ("Use web_search_exa instead"); it ran a web search and returned highlights plus up to 300 characters of text per result. The remote server is https://mcp.exa.ai/mcp and works anonymously with rate limits; an API key or OAuth raises them. The MCP server is MIT-licensed.
Source: github.com/exa-labs/exa-mcp-server (tool definitions in src/tools). Pricing: exa.ai.
Ref
Ref searches "documentation for APIs, services, and libraries": public documentation on the web or GitHub, plus your own private repositories and PDFs. ref_search_documentation returns relevant URLs, and ref_read_url reads one as Markdown, returning "the most relevant ~5k tokens" of the page. The recommended setup is the remote server at https://api.ref.tools/mcp with an API key, which Ref requires. The MCP server is MIT-licensed.
Source: github.com/ref-tools/ref-tools-mcp. Pricing: ref.tools.
JustClaw-It
JustClaw-It searches 1,573,603 components (functions, classes, handlers and modules) mined from open-source repositories. search_components is free and returns ranked matches with a 0-10 quality score and five sub-scores, the SPDX licence, the copyright holder where known, and a GitHub permalink. get_component returns the component's full source with an attribution header. The public library only serves permissive and weak-copyleft code; strong copyleft, unlicensed and unchecked code never reaches it. See How licensing works, Scores & ranking and Credits & plans.
Which one to use
- Your agent needs to know how a library's current API works: a documentation server such as Context7 or Ref.
- Your agent needs anything on the web, from changelogs to blog posts: a web search server such as Exa.
- Your agent is about to write a component that someone has probably built already (auth middleware, a webhook handler, a retry helper), and you need to know whether you may reuse it: JustClaw-It.
They don't overlap much, and plenty of setups run a documentation server alongside JustClaw-It. Each is a separate entry in your MCP client's configuration; see the quickstart.