Connect your AI to Harnace.

One read-only connection for Claude, ChatGPT or any AI that speaks the Model Context Protocol. Your AI reads your company's checked record: the figures, the definitions behind them, the differences between your systems and the records behind any figure. It can read, and nothing more.

The address

Your AI asks you to sign in the first time. Sign in with your email. If you have no Harnace account yet, you make one there and connect your company's systems, starting with its ledger and CRM. Then choose the company your AI may read and allow it.

Claude

On a Free, Pro or Max plan

1. Go to Customize, then Connectors. Choose Add custom connector.
2. Name it Harnace, paste the address above and choose Add.
3. Choose Connect, sign in and choose the company your AI may read.

On a Team or Enterprise plan

1. An Owner goes to Organization settings, then Connectors. They choose Add, then Custom (Web if asked), paste the address and choose Add.
2. Each member then finds Harnace under Customize, then Connectors, and chooses Connect to sign in with their own email. Each person's connection reads only what that person may.

In Claude Code

claude mcp add --transport http harnace https://harnace.com/api/mcp

Then type /mcp in Claude Code, choose harnace and sign in.

ChatGPT

1. Go to Plugins at chatgpt.com/plugins. Choose the plus button, then Add custom MCP server.
2. Name it Harnace and give it a short description, such as "My company's finance data, read only".
3. Under Connection, paste the address above. Choose OAuth for authentication, read the warning and choose I understand and want to continue.
4. Choose Create as a plugin, check that the six tools below are listed, then sign in when ChatGPT asks.

On a ChatGPT Business or Enterprise workspace, an admin may need to allow custom servers first.

Any other AI

Any client that speaks the Model Context Protocol over HTTP and signs in with OAuth can connect. Add the address, and sign in when it asks.

What your AI can do

Six tools, and every one of them only reads. None can change anything, in Harnace or in any of your systems, and each tells your AI so.

• harnace_guideRead onlyThe company's guide: the systems its records come from and how fresh they are, the figures it can be asked for and the definitions in force. Your AI reads it first.
• harnace_query_metricsRead onlyFigures from the checked record, such as ARR and its movements, customer counts, net and gross retention and differences, by month, fiscal quarter or year, each with an id to cite.
• harnace_get_definitionRead onlyHow the company counts a figure: what it includes and leaves out, who owns it, who approved each version and when each is in force.
• harnace_trace_figureRead onlyThe records behind any figure: the source rows, the checks that let them in, the definition version it was counted under and the line in the owner's report it ties to.
• harnace_list_differencesRead onlyWhere two systems that should agree do not, such as the CRM and the ledger, in dollars, with the cause.
• harnace_list_sourcesRead onlyEach system and file the records come from, who owns it and when it was last read.

Ask it about your company

Once your systems are connected, ask in your own words. Three to start with:

• What was our ARR at the end of last month, and what moved it during the month?Beginning and ending ARR with new, expansion, contraction and churn between them, under your ARR definition, cited by query id.
• Where do our CRM and our ledger disagree on a customer's ARR, and why?Each difference in dollars with its cause, such as timing or one customer under two names, cited by the difference's id.
• Which contract lines make up our largest customer's ARR, and what was left out?The lines behind the figure, traced to their records, with anything the definition leaves out, such as a one-time fee.

What is kept, and how to take it back

Every request your AI makes is a row on the company's read ledger: who asked, through which AI, which tool, what it asked for and how many rows came back. Never the answer itself. A company's leaders see every connection on the Your AI page in the console and can revoke any one, and its next request is refused. You can also remove Harnace in your AI's own settings. Nothing about what a person is paid is served on this connection. The privacy page says what is kept and for how long, the terms say how the connection may be used and the security page says how it is protected.

Help

If a connection will not sign in or a figure looks wrong, write to hello@harnace.com, and a founder answers.