Pyunto Diary MCP server

pyunto-agent

<!-- mcp-name: com.pyunto/diary -->

Make an external agent the partner of a Pyunto exchange diary. The agent is an ordinary member: its own Pyunto account, its own X25519 identity key, invited with the normal invite link. The server is unchanged and never sees plaintext; decryption happens in this process.

Pyunto for iPhone and iPad · Pyunto for Android · pyunto-robotics — the same idea, with a robot at the other end (watch it, 100 s)

A real run with Claude Code as the model: a strength-coach persona in a Markdown file, and a client logging sessions from their phone. The second reply compares with the day before. Watch the full 90-second video.

Two kinds of agent

The same package, the same account, the same keys. What differs is who starts the conversation.

1. Agent — it writes to your users

You write; it replies, unprompted, in the same thread.

your phone                     your computer
 ┌───────────────┐            ┌──────────────────────┐
 │  Pyunto app   │            │  pyunto-agent run    │
 │               │            │                      │
 │  "tough day   │  ───────▶  │  reads the entry     │
 │   at work"    │  encrypted │  decrypts it HERE    │
 │               │            │        │             │
 │               │            │        ▼             │
 │  "that sounds │  ◀───────  │  Claude API, or      │
 │   exhausting" │  encrypted │  Claude Code, or     │
 └───────────────┘            │  your own HTTP URL   │
                              └──────────────────────┘
        │                                │
        └────────  api.pyunto.com  ──────┘
              (ciphertext only, never plaintext)

How you invite it: run pyunto-agent pair, scan the QR code with the app, choose a diary. The agent starts answering as soon as you approve.

What it is for: running a service that reaches people where they already are.

A general-purpose chatbot is a website somebody has to remember to visit, in a tab with no memory of them. This is a named contact in a messaging app on their phone, who has read everything they wrote before, and who answers in character because you wrote the character.

That character is a file. --persona coach.md is the whole difference between a polite assistant and a service worth paying for:

You are a strength coach. Your client logs every session here.

- Hold them to the programme. If they skipped legs again, say so plainly.
- Always ask for the numbers: weight, sets, reps. A session without numbers is not logged.
- Compare against last week before you praise anything.
- No pep talk. One sentence of encouragement, only when it is earned.

pyunto-agent run --backend claude-api --persona coach.md

Some shapes this takes:

Shortened. The full README is on GitHub.