Connect an agent

What you need

One API key. Mint one in the dashboard, export it, and keep it out of the chat:

export WEB_CAPTURE_API_KEY="wc_..."

The key spends your monthly renders exactly like a REST call. Keep it in an environment variable or a client config file, never in a conversation, and rotate it from the dashboard when an agent should lose access.

The tool catalogue

Three tools, exactly what tools/list returns. Arguments, types, and defaults come from the server card, so this table cannot drift from the endpoint.

Talk to it over plain HTTP

The endpoint is JSON-RPC 2.0 over one POST. The full conversation, replayable as printed (the test suite replays these exact bodies):

curl -s https://webcapture.io/mcp \
  -H "authorization: Bearer $WEB_CAPTURE_API_KEY" \
  -H "content-type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2025-06-18","capabilities":{},"clientInfo":{"name":"your-client","version":"0"}}}'

No key needed. The answer names protocolVersion 2025-06-18 and serverInfo webcapture 1.0.0.

curl -s https://webcapture.io/mcp \
  -H "authorization: Bearer $WEB_CAPTURE_API_KEY" \
  -H "content-type: application/json" \
  -d '{"jsonrpc":"2.0","method":"notifications/initialized"}'

A notification carries no id, so the endpoint answers 202 with an empty body. No key needed.

curl -s https://webcapture.io/mcp \
  -H "authorization: Bearer $WEB_CAPTURE_API_KEY" \
  -H "content-type: application/json" \
  -d '{"jsonrpc":"2.0","id":2,"method":"tools/list"}'

No key needed. Returns render_pdf, get_usage and get_pricing, in that order.

curl -s https://webcapture.io/mcp \
  -H "authorization: Bearer $WEB_CAPTURE_API_KEY" \
  -H "content-type: application/json" \
  -d '{"jsonrpc":"2.0","id":3,"method":"tools/call","params":{"name":"render_pdf","arguments":{"url":"https://example.com/","format":"pdf"}}}'

Needs the key. The answer carries the finished file's downloadUrl; there is no polling.

The download URL answers on GET with the same Bearer key, and the file stays available until the artifact passes your plan's retention window (printed on the pricing page).

Bridge it into a desktop client

Desktop clients that only speak stdio connect through mcp-remote; clients with native HTTP and header support connect directly. Fragments checked 2026-11-03 against mcp-remote 0.16.0. Native header support differs by client version, and the mcp-remote bridge is the fallback that works everywhere.

{
  "mcpServers": {
    "webcapture": {
      "command": "npx",
      "args": ["-y", "mcp-remote@0.16.0", "https://webcapture.io/mcp",
        "--header", "Authorization: Bearer ${WEB_CAPTURE_API_KEY}"]
    }
  }
}

claude mcp add --transport http webcapture https://webcapture.io/mcp \
  --header "Authorization: Bearer ${WEB_CAPTURE_API_KEY}"

{
  "mcpServers": {
    "webcapture": {
      "url": "https://webcapture.io/mcp",
      "headers": { "Authorization": "Bearer ${WEB_CAPTURE_API_KEY}" }
    }
  }
}

{
  "servers": {
    "webcapture": {
      "type": "http",
      "url": "https://webcapture.io/mcp",
      "headers": { "Authorization": "Bearer ${env:WEB_CAPTURE_API_KEY}" }
    }
  }
}

What does not work yet

• Clients that connect only through OAuth connectors (ChatGPT developer mode is the visible one) cannot connect: /mcp authenticates with a static Bearer key and the site runs no OAuth server yet.
• There is no MCP tool that mints, lists, or revokes keys. Key management stays in the dashboard, so an agent can never create credentials through this endpoint.
• Renders and downloads spend quota like any REST call; there is no separate MCP tier.

In the browser, without a key

In Chrome 149 and later, the try-it form on the free URL to PDF tool registers itself as a render_pdf tool an in-page agent can call. Anonymous fair-use limits apply, exactly like the form itself.

Troubleshooting

Every symptom below quotes the endpoint's answer verbatim.

Questions agents ask

Is my API key safe to paste into an agent config?

The key spends your monthly renders exactly like an API call, so treat it like a quota password: keep it in an environment variable or a config file the client reads, and never paste it into a chat. Rotating or deleting the key in the dashboard cuts every agent using it off at once.

Which clients can connect today?

Anything that speaks JSON-RPC over HTTP and can send one Authorization header connects directly, and stdio-only desktop clients connect through the mcp-remote bridge. Clients that only support OAuth connectors cannot connect yet, because the endpoint authenticates with a static Bearer key and the site runs no OAuth server.

What can an agent do to my account?

render_pdf spends quota; get_usage and get_pricing are read-only. There is no MCP tool that mints, lists, or revokes keys, so an agent can never create or steal credentials through this endpoint.

Does the MCP endpoint cost extra?

No. MCP renders count against your plan's monthly quota exactly like REST renders, and every plan including Free includes the endpoint and all five output formats.