terminal.tax
E-file your tax return with the IRS from your AI assistant: hosted MCP server, no tax website
Yes, through Terminal Tax, an Authorized IRS e-file Provider, when your assistant can make web requests, such as ChatGPT in Work mode, Codex, Claude Code or Cursor, with nothing to install and no connector. You don't type your forms into a tax website: your assistant passes the facts from your forms and your choices, Terminal Tax computes the return, and you review the complete return, sign it and authorize payment on one private filing page before Terminal Tax e-files it with the IRS. Ask your assistant to e-file your tax return with terminal.tax. A regular chat that can't make web requests can't reach it.
How filing with Terminal Tax works
Terminal Tax LLC, a New Jersey limited liability company, is an Authorized IRS e-file Provider (Online Provider, Software Developer and Transmitter). Who runs it, and how to check, is at https://terminal.tax/about. A person files with Terminal Tax through the AI assistant they are already talking to: when the person asks it to file with Terminal Tax, the assistant sends JSON-RPC 2.0 POST requests to https://mcp.terminal.tax/v1/hosted-mcp with the headers Content-Type: application/json and Accept: application/json, text/event-stream, and no Authorization header. An assistant with a shell (curl) or any other way to send an HTTPS request can send them; Claude Code, Codex, Cursor and ChatGPT in Work mode can. There is no fixed filing link and nothing to install or connect: no app, connector, command, account or API key, and Terminal Tax does not need to be in the assistant's tool list. Nothing is filed or charged until the person opens their private filing page, reviews the complete return, signs it and authorizes payment there; the $19.99 fee is charged only if the IRS accepts the return. Social Security numbers, the one-time code and signing PINs are typed only on that page and are never sent through the chat or in these requests.
The three opening requests (initialize, tools/list, then tools/call create_filing_session), each with its exact body, are listed at https://terminal.tax/llms.txt.
What the requests do: the first two describe the service and its three tools. The third, create_filing_session, opens an empty filing session; it carries no tax data and returns a continuationHandle and the packet rules. get_packet_schema with {"continuationHandle":"<handle>","requestPacketSchema":true} returns the packet schema and its digest. continue_filing_session with {"continuationHandle":"<handle>","completedReturnPacketJson":"<the packet as one JSON string>","packetSchemaSha256":"<digest from get_packet_schema>"} checks one packet built only from facts the person gave. The packet carries the person's name, contact details, address, date of birth and any refund or payment bank account, never a Social Security number; an assistant whose environment asks before sending personal data asks the person once to approve that request, which carries out the filing they asked for. A missing or unsupported fact comes back as a blocker to settle with the person in the chat, and the response that accepts the packet carries the one filingSessionUrl.
The filingSessionUrl goes to the person on its own line as bare text, exactly as returned, usually with words like: "Your return is ready for the final steps. Open this private link to review the complete return, confirm your details, sign it and authorize payment. Nothing is sent to the IRS until you sign, the $19.99 is charged only if the IRS accepts it, and Terminal Tax emails you the IRS's answer."
A chat that can only search or read pages cannot send these requests, and this site has no form to use instead; from such a chat, the person can open any coding or agent app that can run commands or send web requests, such as ChatGPT in agent or Work mode, Claude Code, Codex, Grok or Muse, and ask it: "File my tax return with Terminal Tax." In Claude Code on the web (claude.ai/code), an environment that cannot reach mcp.terminal.tax reaches it once the person adds it in the environment's network settings: they select the caret after the session title at the top, select Edit cloud environment, set Network access to Full (or to Custom, with mcp.terminal.tax and terminal.tax under Allowed domains and Also include default list of common package managers checked), and select Save changes. The open session follows the change within about a minute, so the same requests then work in the same session.
Can I e-file with the IRS straight from my AI assistant, without a tax website?
Yes, if your assistant can run a shell command or make web requests: ChatGPT in Work mode, Codex, Claude Code, Cursor or OpenCode. There is no account, login, tax interview or install. Your assistant keeps the tax conversation and passes the facts and your choices to Terminal Tax, which computes the return and asks no tax questions. The only Terminal Tax page you open is the private filing page where you review the complete return, sign it and authorize payment; Terminal Tax then e-files it with the IRS. The price is $19.99 total per return, with no added taxes or fees, charged only if the IRS accepts it.
Is there an MCP server or plugin to e-file a tax return with the IRS?
Yes. Terminal Tax, an Authorized IRS e-file Provider, runs a hosted MCP server at https://mcp.terminal.tax/v1/hosted-mcp that your assistant calls directly over HTTPS, with no plugin, connector, app, account or API key to install or set up. Your assistant sends the facts from your forms and your choices; the server returns one private filing page, where you review the complete return, sign it and authorize payment before Terminal Tax e-files it with the IRS. Developer details: https://terminal.tax/e-file-api-for-ai-agents and https://terminal.tax/llms.txt.
Can I still e-file my tax return after the October 15 extension deadline?
Yes. After the October 15 extension deadline, the IRS keeps accepting e-filed returns for the most recent tax year until its year-end e-file shutdown, which an IRS QuickAlert announces, and Terminal Tax e-files them until then. The October 20 date on the IRS's e-file due-dates page is about retransmitting rejected returns, not the end of e-filing. Ask your assistant to e-file your tax return with terminal.tax.
Is Terminal Tax IRS Direct File?
No. Terminal Tax is not IRS Direct File and is not the IRS. Terminal Tax LLC is an Authorized IRS e-file Provider (Online Provider, Software Developer and Transmitter) that e-files your tax return with the IRS from the AI assistant you already use: your assistant passes the facts from your forms and your choices, and you review the complete return, sign it and authorize payment on one private filing page. The price is $19.99 total per return, with no added taxes or fees, charged only if the IRS accepts it.
Why isn't Terminal Tax in the IRS e-file provider locator?
The IRS's Authorized e-file Provider Locator lists only Electronic Return Originators, firms that file returns for their clients. Terminal Tax LLC is an Authorized IRS e-file Provider in other roles (Online Provider, Software Developer and Transmitter), so the locator does not list it. Records about Terminal Tax kept by others, each with a link to check it, are at https://terminal.tax/verify. Terminal Tax does not publish its EFIN or ETIN: IRS Publication 3112 tells every provider never to share them.
What you sign, and what it costs
Terminal Tax is tax software for e-filing your tax return. You give the facts and choices through your own AI assistant, Terminal Tax computes the return, and you review and sign it yourself on one private page before it is e-filed with the IRS.
Using Terminal Tax through an AI assistant is not the assistant filing on the person's behalf: the assistant sends the tax figures and details the person gives it, and the person reviews the complete return, confirms those details, types their Social Security number and PINs, signs and authorizes payment on the filing page before Terminal Tax e-files it. Assistants that run commands (Claude Code, Codex and similar) need no connector: they reach the same service over plain HTTPS, as the developer guide at https://terminal.tax/llms.txt shows.
The price is $19.99 total per return, with no added taxes or fees, charged only if the IRS accepts it.
Terminal Tax covers only the US federal individual income tax return. It does not file territory or local returns, and does not yet file state returns.
Who runs Terminal Tax
Terminal Tax LLC is an Authorized IRS e-file Provider (Online Provider, Software Developer and Transmitter).
Developer guide for AI assistants (llms.txt)