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Add SpecStream to fx, the coding agent from Vercel Labs, with one /mcp add line. fx signs you in through your browser, and the agent can search the live web, read whole pages and build lists with the source on every value.

SpecStream for fxCoding agents

What you need

  • fx, installed with curl -fsSL https://fx.sh/setup.sh | bash.
  • A SpecStream account. New accounts get $10 of credit, no card.

  1. 1. Add SpecStream

    Start fx and add the server by its name and address. A URL means a remote server, so there is no transport to choose. fx saves the entry in ~/.fx/mcp.json, where it applies to every project:

    In fx
    /mcp add specstream https://api.specstream.ai/mcp

  2. 2. Sign in to SpecStream

    SpecStream asks for a sign-in, so fx opens your browser right away. Sign in to SpecStream or create an account, and approve the access fx asks for. fx registers itself with SpecStream, so there is no client ID to enter, and it saves the login and renews it.

    If the browser didn't open, select Open the sign-in page in the transcript. Over SSH, run fx mcp login --no-browser specstream, open the address it prints on any device, and paste back the address your browser ends up on.

  3. 3. Check the connection

    /mcp show specstream connects and lists SpecStream's tools. fx names each one mcp_specstream_ followed by the tool, such as mcp_specstream_search_web.

    In fx
    /mcp show specstream

  4. 4. Ask fx

    Ask for something current and name SpecStream. fx finds the tools through its toolbox when a turn needs them:

    In fx
    Use SpecStream to find the current stable release of Zig and read its release notes.

  5. 5. Or connect with an API key

    Use a key in CI, in fx ask scripts, or on a machine with no browser. In the workspace, open Agents & API, choose API keys, then Create API key, and set a total limit.

    SpecStream takes the key as a Bearer token. fx's header_env field can't set Authorization, and a profile entry refuses a literal Authorization header, so the key goes through bearer_token_env. Put this entry under mcpServers in ~/.fx/mcp.json, export SPECSTREAM_API_KEY, and start fx from the same terminal. If the variable is missing, /mcp list shows the server as needing it.

    ~/.fx/mcp.json
    {
      "mcpServers": {
        "specstream": {
          "type": "http",
          "url": "https://api.specstream.ai/mcp",
          "bearer_token_env": "SPECSTREAM_API_KEY"
        }
      }
    }

What fx gets

SpecStream's server at https://api.specstream.ai/mcp adds these tools.

  • search_web answers a question from the live web, with up to 10 results for $5 per 1,000 searches. A search that returns nothing costs nothing.
  • read_pages returns the main text of up to 20 pages or documents (PDF, Word, Excel) in one call, at $0.80 per 1,000 pages. A page that gives no text is not charged.
  • Deep Search builds a list from a request in plain words. compile reads the request back, quote_capacity_work prices it for free, and authorize_capacity_work starts it only after you approve the maximum. get_find and list_find_rows read the rows, each with its source URL and read time.

fx's own web search and SpecStream

fx's built-in web_search needs AI Gateway, which searches with Exa. With a ChatGPT or Grok subscription, or a custom connection such as Ollama or OpenRouter, fx can't search the web at all. SpecStream gives fx web search and page reading on any model connection.

SpecStream's Search API scores 97.9 F-score on all 1,000 SimpleQA Verified questions and 64.0 item F1 on all 200 WideSearch tasks. The method is on benchmarks.

Approvals in fx

MCP calls follow fx's permission mode and rules. To have fx ask you before a paid list starts, add {"permission": {"mcp_specstream_authorize_capacity_work": "ask"}} to ~/.fx/settings.json. Searches and page reads are charged per call with no quote. Deep Search adds its own gate: nothing paid starts until you approve the price SpecStream quotes.

Large results in shell commands

A finished list can hold more rows than a conversation needs. In a command fx's shell tool runs, fx mcp call runs a SpecStream tool and writes its result to a file, so only what the command prints reaches the model. fx mcp call help mcp_specstream_list_find_rows prints the arguments the tool takes.

Cost

Connecting SpecStream to fx is free, and new accounts start with $10 of credit. A search of up to 10 results costs $5 per 1,000, and a page read costs $0.80 per 1,000. Deep Search is priced per delivered row and quoted before it runs, and a run can't cost more than the maximum you approved. See pricing and how billing works.

Remove

Run /mcp remove specstream in fx, or fx mcp remove specstream in a terminal. It removes the entry and its saved login. To end the access on SpecStream's side, open Agents & API in your workspace and revoke fx under OAuth applications, or revoke the key under API keys. Questions: [email protected].

More

SpecStream for fx covers what it does in fx on one page. Every other tool has its guide in Connect your tools. You see the most a request can cost before it starts, and the matches are paid from your balance. Billing has the details. For help, email [email protected].