Context7 Account Broker

A drop-in Context7 MCP proxy for people who use more than one authorized API key. It balances requests by quota usage, keeps each library on the same account, and caches successful responses on disk.

OpenCode sees the standard Context7 tools:

• resolve-library-id

• query-docs

The broker handles account selection, failover, caching, and quota refreshes without changing tool schemas or results.

What it does

• Routes new work to the account with the lowest proportional quota usage.

• Keeps a library on the same account within each project.

• Fails over when an account is blocked, rate limited, unauthorized, or temporarily unreachable.

• Reads Context7's RateLimit-* headers instead of estimating quota locally.

• Caches exact successful calls for 30 days by default.

• Coalesces concurrent identical requests into one upstream call.

• Stores named credentials in a private 0600 configuration file.

• Provides CLI commands for account management, quota status, and diagnostics.

Related MCP server: MCP Gateway

Quick start

1. Add your Context7 accounts

The command prompts for the API key without displaying it:

npm_config_allow_git=all npx -y \
  git+https://github.com/mirsella/context7-account-broker.git \
  accounts add personal

Repeat the command with a different name for each account. To verify the saved accounts without exposing their keys:

npm_config_allow_git=all npx -y \
  git+https://github.com/mirsella/context7-account-broker.git \
  accounts list

2. Configure OpenCode

Add the server to ~/.config/opencode/opencode.jsonc:

{
  "mcp": {
    "context7": {
      "type": "local",
      "command": [
        "npx",
        "-y",
        "git+https://github.com/mirsella/context7-account-broker.git"
      ],
      "environment": {
        "npm_config_allow_git": "all"
      },
      "timeout": 30000,
      "enabled": true
    }
  }
}

Restart OpenCode, then check the connection:

opencode mcp list

npm_config_allow_git=all is required by npm 12, which blocks Git package sources by default. It permits the GitHub package used by this MCP entry.

CLI

The examples below use the GitHub version directly.

For example:

REPO=git+https://github.com/mirsella/context7-account-broker.git

npm_config_allow_git=all npx -y "$REPO" status
npm_config_allow_git=all npx -y "$REPO" config
npm_config_allow_git=all npx -y "$REPO" accounts remove personal

For non-interactive account setup:

printf '%s\n' "$CONTEXT7_API_KEY" |
  npm_config_allow_git=all npx -y "$REPO" accounts add personal

Account selection

At startup, the broker probes each key and reads Context7's authoritative RateLimit-Limit, RateLimit-Remaining, and RateLimit-Reset headers.

For a library without an existing assignment, it chooses the available account with the lowest proportional usage:

used / limit = (limit - remaining) / limit

Equal accounts rotate in round-robin order. Once selected, the account is saved as the preferred account for that library and project. A temporary failure can move one request elsewhere without discarding the preference.

Blocked accounts are checked again at their reset time. Free-plan accounts are also checked at the next UTC day so Context7's daily bonus calls can become available.

Cache

Successful tool results are cached by:

• project scope

• tool name

• canonicalized arguments

• API-key hash

The API-key partition prevents a removed account from serving its cached private content. Expired files are removed on startup and lazily when read. Concurrent identical calls share one in-flight request.

The default cache directory is:

~/.cache/context7-account-broker

Delete that directory to invalidate all cached results and affinities.

Credentials

Named accounts are stored at:

~/.config/context7-account-broker/accounts.json

The directory uses mode 0700 and the file uses mode 0600.

When this file contains accounts, it acts as an allowlist. Inherited CONTEXT7_API_KEY and CONTEXT7_API_KEYS values are ignored unless CONTEXT7_BROKER_INCLUDE_ENV=1 is set. This prevents an unrelated shell key from silently joining a configured pool.

With no configured account file, the broker accepts:

export CONTEXT7_API_KEYS='ctx7sk_first,ctx7sk_second'

Configuration

Quota cost

Context7 attaches quota state to normal API responses rather than exposing a free status endpoint. Each startup probe, refresh, and status check consumes one API request per checked account.

Development

Requirements: Node.js 20 or newer and pnpm.

git clone https://github.com/mirsella/context7-account-broker.git
cd context7-account-broker
pnpm install
pnpm typecheck
pnpm test
pnpm build

Run the local binary:

node dist/index.js accounts list
node dist/index.js status
node dist/index.js serve

Responsible use

Use API keys only for accounts you own or are authorized to aggregate. Follow Context7's terms and plan limits. The broker does not create accounts, bypass authentication, or hide upstream failures.

License

MIT