Since.dev

Since.dev MCP

What changed in the packages, APIs and services your code depends on, and the fixes it needs.

Product · Documentation · MCP reference

Since.dev tracks every package in 18 registries, every AI model's retirement on each platform that serves it, API changes and runtime end-of-life dates, each with its source. This repository connects your agent to it: a hosted remote MCP server, plus a plugin for Claude Code, Cursor and Codex that tells the agent when to use it. There is no server code to install or run.

Install

Every install signs in through your browser (OAuth). You approve the client for one Since.dev workspace, and no key is stored in a file. A free account works.

Claude Code

Install the plugin, which adds the server and four skills:

/plugin marketplace add since-dev/mcp

/plugin install since-dev@since-dev

Or add only the server, then run /mcp to sign in:

claude mcp add --transport http since https://api.since.dev/mcp

Cursor

Click Add to Cursor above, or add this repository as a plugin to get the server, the skills and a rule that checks dependency, model and runtime changes.

VS Code

Click Install in VS Code above, or run:

code --add-mcp '{"name":"since","type":"http","url":"https://api.since.dev/mcp"}'

Codex

Install the plugin:

codex plugin marketplace add since-dev/mcp

Or add only the server and sign in:

codex mcp add since --url https://api.since.dev/mcp

codex mcp login since

Gemini CLI

gemini extensions install https://github.com/since-dev/mcp

The extension asks for a workspace API key (see below). To sign in through the browser instead, add the server directly:

gemini mcp add --transport http since https://api.since.dev/mcp

Any other MCP client

Add a remote server with this URL over Streamable HTTP and sign in when the client asks:

https://api.since.dev/mcp

For a client that reads an mcpServers file, see examples/mcp.json. For VS Code's .vscode/mcp.json, see examples/vscode-mcp.json.

Use an API key instead

Some clients can't sign in through a browser. For those, create a key and send it as a Bearer token:

1. Sign in at https://app.since.dev and pick the workspace the agent should use.
2. Open API keys (https://app.since.dev/api-keys) and choose Create API key. The key starts with sc_live_ and is shown once.
3. Add the header Authorization: Bearer in your client's secret settings. Never commit a key.

A key reaches only its own workspace, over the API and MCP, and any member with a seat can revoke it under API keys.

What's inside

• The server: 3 tools, from the same record as the Since.dev API. whats_changed and check_code only read, so your client runs them without asking. fix_code opens fix pull requests, so your client asks before every call.
• Skills (Claude Code, Cursor, Codex and other clients that read Agent Skills): since-before-upgrading, since-model-retirements, since-what-changed, since-ci-and-runtimes. They tell the agent when to check: before upgrades, when code names a model, before writing against something it learned in training, and when editing CI or runtimes.
• A Cursor rule (rules/since.mdc) that brings the same checks to manifest, lockfile, Dockerfile and workflow edits.

Tools

tools/list returns each tool's full input schema.

Tools

whats_changed and check_code only read, and both work on every plan; checking a connected repository (check_code with repo) is on the Business and Platform plans. fix_code writes: with code it returns a patch, on the Team plan and up, and with repo it opens fix pull requests for a person to review, on the Business and Platform plans. Each call costs credits; a bad input or a call the plan does not include is refused with a plain sentence and costs nothing.

Examples

Each step shows the name and arguments the agent sends in a tools/call request.

1. Before writing code against a model, check the id:

   { "name": "check_code", "arguments": { "model": "<model id>" } }

The result lists the model's status (supported, deprecated, retired or unknown) and a finding for each change that applies, with its severity, daysLeft, replacement and cited source.

1. Before upgrading a package, read what changed from the version you have:

   { "name": "whats_changed", "arguments": { "package": "npm:react", "since": "18.2.0" } }

Each change carries its canonical surface, kind, severity, dates, replacement and evidence. package.releasesBehind says how far behind the version is, and coverage says which sources were read and how fresh they are. Page with nextCursor.

1. See what retires in the next 90 days for a provider:

   { "name": "whats_changed", "arguments": { "provider": "anthropic", "within": "90d" } }

1. Fix what a connected repository's check found (your client asks first):

   { "name": "fix_code", "arguments": { "repo": "<repository id>" } }

Treat unknown and needs_review as not settled, never as fine.

Requirements

• A Since.dev account. Create one with email, GitHub or Google. Each account includes one Free workspace.
• Credits. Each call costs credits from the workspace's monthly allowance, and every response says how many are left. See pricing.

Support

• Documentation: https://since.dev/docs, including the MCP reference
• Questions about this connection: open an issue
• Email: support@since.dev

License

The files in this repository are MIT licensed. See LICENSE.