SignWith: E-signatures without the subscription. Pay per doc.

Credit packs come in three sizes: $9 for 10 credits, $19 for 25 and $29 for 50. That works out to $0.90, $0.76 and $0.58 per signed document. A credit is spent only when a document is fully signed, regardless of how many people sign it. Packs stay valid for 12 months, and the three free documents each month do not roll over. A $199 lifetime deal offers unlimited signed documents. The founders say more than 1,000 people use it and 5,000 documents have been signed. The MCP server is the AI angle. It exposes 18 tools covering documents, signers and credits. Claude, ChatGPT, Cursor and VS Code can connect to it through a sign-in flow with no API key. The assistant is set to ask for confirmation before sending, reminding or cancelling anything. The REST API and MCP use the same credits, with no developer plan. The company's own comparisons show where the model loses: a user signing six documents every month is better off on BoldSign's free tier. There are also no team seats yet, though team accounts are listed as coming. For AI builders, agent-driven workflows such as drafting a contract and sending it for signature need a signing back end that bills per action and lacks seat licences. Per-document pricing fits that usage pattern better than per-user subscriptions. It also shows how small SaaS tools are adding MCP servers as a distribution channel.