# Ask Claude whether a song is registered > Free MCP server for Claude and other AI assistants: ISRC lookup, MLC registration checks, ISWCs, songwriters and publishers, and CWR validation. No account. *Published by [TrackForge](https://trackforge.studio)* **Page:** https://trackforge.studio/mcp **Server address:** `https://api.trackforge.studio/api/v1/mcp` (Streamable HTTP, no sign-in) **Last updated:** 2026-10-04 --- ## MCP server for AI assistants TrackForge runs a free MCP server that gives Claude and other AI assistants an ISRC lookup, a registration check against The MLC’s data, a song’s ISWCs, songwriters and publishers, and CWR validation. It is a way to see whether music royalties may be going unmatched or unclaimed. No account and no API key. --- ## What you can ask Real answers from the server on 3 October 2026, shortened. An assistant puts them in its own words. ### “Is ISRC USIR20400274 registered with The MLC, and is any share unclaimed?” - **Verdict:** registered, high confidence - **Evidence:** Recording linked to MLC work M1972U, “MR. BRIGHTSIDE”, ISWC T0721040692 - **MLC data as of:** 29 September 2026 - **Next step:** No gap found by this check as of 2026-09-29. ### “Who wrote the song on that recording, and which label first released it?” - **Writers:** Brandon Flowers and Dave Keuning, each with an IPI number - **Publishers:** The Killers Publishing; Universal Music Publishing Ltd. - **Earliest release:** “Mr. Brightside”, 29 September 2003, Lizard King Records, catalogue number LIZARD007X - **Source:** MusicBrainz, which lists 188 releases of the recording ### “Check these ISRCs against The MLC and tell me which have no linked work.” - **Summary:** 5 checked: 3 registered and 2 with no linked work, both at low confidence - **For each ISRC:** A verdict, a confidence and a next step - **No linked work:** “the rightsholder can register the work, or match this recording to an existing registration, with The MLC” - **MLC data as of:** 29 September 2026 Five ISRCs were sent. One request takes up to 50. ### “Here is the CWR file I am about to send. Is it valid, and what should I fix?” - **Result:** Not valid: 1 error and 1 warning in 1 transaction - **Line 3, error:** Work title is blank. Every NWR/REV record must have a non-empty work title (positions 20-79). - **Line 4, warning:** Publisher IPI Name # fails its check digits. That normally means a typo or a transposed digit. - **Always stated:** Validation does not guarantee acceptance by a society. The file was a made-up test file with its title removed. ### Ask for a person If you want someone at TrackForge to look at your catalogue, say so and agree to be contacted. The assistant records your name and email address, and a person replies by email. Nothing is sent automatically. --- ## Having a publisher does not mean your songs are registered A publisher or administrator on record shows a relationship, not a finished registration. The MLC collects US mechanical royalties from streaming and download services, and it can pay them out only when a recording is linked to a registered work with its shares claimed. This server checks that link, recording by recording. - **Start from what you have.** An ISRC, a Spotify track link, a song title or a YouTube link. - **Dated evidence.** Every MLC answer comes from TrackForge’s copy of The MLC’s public bulk data and carries the date it is true as of. - **A next step.** When no work is linked, the answer says whether to match the recording to an existing work or register one, and who can do it. - **Free, with no account.** No sign-in and no API key. ### How to read an answer - `registered` -- The recording is linked to one MLC work with nothing unclaimed or in dispute. - `partial` -- The recording is linked to one work, and a share is unclaimed or in dispute. - `nobody` -- No MLC work is linked to the recording. That does not by itself mean the work is unregistered: the next step says whether to match or register. - `conflict` -- The recording is linked to more than one MLC work. - `unknown` -- The data could not be read. It is never a negative finding. --- ## How to add it ### Claude 1. In Claude, open Customize, then Connectors. 2. Select Add, then Add custom connector. 3. Give it a name, paste the server address and select Continue. Claude shows No sign-in as detected. Select Add. 4. On the connector’s page, select Connect. 5. Ask your question in a new conversation. The first time each tool is used, Claude asks whether to allow it. Claude's connectors page: https://claude.ai/customize/connectors These steps were checked on a Max plan on 3 October 2026. Claude’s screens can differ between plans and change; the server address and No sign-in are all it needs. Custom connectors work on Free, Pro and Max plans, and the Free plan allows one. On Team and Enterprise plans an Owner adds it first under Organization settings, Connectors, and members then select Connect. ### Other MCP clients Any client that supports remote MCP servers over Streamable HTTP can use the same address with no authentication. In Claude Code: ```bash claude mcp add --transport http trackforge-isrc-lookup https://api.trackforge.studio/api/v1/mcp ``` --- ## Limits and privacy Each session has 60 usage units per 5 minutes and 600 a day. A lookup costs 1 unit, a catalogue check 1 unit per 5 ISRCs and a CWR validation 2. A catalogue check takes up to 50 ISRCs and a CWR file up to 256 KB. Each call is logged for usage measurement: the tool, the kind of input, the ISRCs looked up, the outcome, the assistant’s name and version, and a keyed one-way hash of the address, never the address itself. Titles, artist names and CWR file content are not logged. Contact details are stored only when you ask for a follow-up. The full terms are in the [Privacy Policy](https://trackforge.studio/privacy) and the [Terms of Service](https://trackforge.studio/terms). ### What it is not - Answers are findings from registration data as of the date shown. They are not legal advice and not a statement of who owns a song or who may use a recording. - The registration check reads The MLC’s data, which covers US mechanical royalties. It holds no PRS for Music, PPL or SoundExchange data. - Writer, publisher, ISWC and release details come from MusicBrainz’s public-domain core data. Its community edits that data, so it is evidence, not proof. - A Spotify link is used only to find the recording’s ISRC. Spotify’s own data is not returned. - TrackForge is independent of Anthropic, The MLC, MusicBrainz and Spotify, and none of them endorses this server. --- ## Questions ### What is the TrackForge MCP server? It is a free remote MCP (Model Context Protocol) server at https://api.trackforge.studio/api/v1/mcp. It gives Claude and other AI assistants four tools: an ISRC lookup with a registration check against The MLC’s data, a catalogue check for up to 50 ISRCs, CWR 2.1 file validation, and a way to ask a person at TrackForge to follow up. No account or API key is needed. ### How do I check whether a song is registered with The MLC using Claude? Add https://api.trackforge.studio/api/v1/mcp as a custom connector in Claude under Customize, Connectors, then ask with an ISRC, a Spotify track link or a song title. The answer gives a verdict (registered, partial, nobody, conflict or unknown), the date the MLC data is true as of, and a next step. ### Does it tell me who owns a song? No. It reports what registration data shows: whether a recording is linked to a work in The MLC’s data, whether a share is unclaimed, and the songwriters and publishers MusicBrainz records. Those are findings as of the date shown, not legal advice and not a statement of ownership. ### Where does the data come from, and how current is it? MLC answers come from TrackForge’s copy of The MLC’s public bulk data, refreshed weekly, and every answer carries the snapshot date. Writer, publisher, ISWC and release details come from TrackForge’s copy of MusicBrainz’s public-domain core data, refreshed about twice a month. The server never queries The MLC live. ### Is it free, and is there a limit? It is free and needs no account. Each session has 60 usage units per 5 minutes and 600 a day: a lookup costs 1 unit, a catalogue check 1 unit per 5 ISRCs and a CWR validation 2. A call over a limit returns a message saying how long to wait. --- ## Help and documentation - [MCP server documentation](https://trackforge.studio/certification/technical/mcp-server) -- Every tool, input and limit, and how to read each verdict. - [auth.md](https://trackforge.studio/auth.md) -- The same details in a form for automated clients. - [ISRC Lookup](https://trackforge.studio/isrc-lookup) -- The same check in your browser, with CSV and PDF export. - [CWR Workbench](https://trackforge.studio/cwr-tool) -- Create, check and read CWR files in the browser, including files over 256 KB. - [Support](https://trackforge.studio/support) -- How to read an answer, and who to contact. - [Registry entry](https://trackforge.studio/.well-known/mcp/server.json) -- The server’s description for MCP registries: studio.trackforge/isrc-lookup. ## Continue reading - [ISRC Registration Gaps](https://trackforge.studio/research/isrc-registration-gaps) -- How the gap between Spotify coverage and MLC work registration leaves mechanical royalties unpaid. - [The Unclaimed Economy](https://trackforge.studio/research/unclaimed-economy) -- Works with unclaimed US mechanical royalties at The MLC, cross-referenced against other sources. - [What is CWR?](https://trackforge.studio/certification/cwr/what-is-cwr) -- The Common Works Registration format, and how a work reaches a society. --- Source: [https://trackforge.studio/mcp](https://trackforge.studio/mcp)