Setup

OpenProse runs where your agent already lives. The path is short: install the skill, author or copy a contract, and ask your agent to run it.

1. Install the skill

npx skills add openprose/prose

That installs the open-prose skill into any Prose-Complete coding agent (Claude Code, Codex CLI, OpenCode, and friends). The skill teaches the session the language: the contract grammar, the compile behavior, and the execution semantics. The contract may still require tools, credentials, inputs, and permissions from the host.

2. Author your first contract

Start with what the agent must accomplish and what conditions its work must satisfy. In the public skill format, write those requirements in a Markdown file with kind: frontmatter and recognized ### sections. Save this introductory example as competitor-funding.prose.md:

---
name: competitor-funding
kind: responsibility
---

### Goal

Keep a current, corroborated funding view for every tracked competitor.

### Maintains

A funding view per competitor: each carries a stable `name`, a set of funding
events (round, amount, date), and a `last_corroborated` field. Material: the
event set (unordered) and each event's round, amount, and date. Immaterial
everywhere: `fetched_at` and source request ids. Postcondition: every funding
event cites a source.

This example states the desired result and source-evidence requirement. Supply the tracked competitors and permitted data access in the running environment; configure a continuity policy and serving host if it must stay current over time.

Reuse kind: gateway contracts for external ingress and kind: function contracts for stateless helpers. Use ### Requires when a responsibility subscribes to another contract's facets. Contracts teaches the format, and Contract authoring explains requirements, discretion, and composition.

3. Run it

Point your agent at the file and say:

prose run competitor-funding.prose.md

This is an instruction to the session, not a shell binary. A skill-loaded session carries out the VM instructions: it resolves the contract, spawns renders, maintains the world-model, and records the run using the available host capabilities. See Harness-agnostic for why there is no parser and what a host must provide.

4. Learn from the examples

The fastest way to pick up the idiom is to read working contracts. The skills/open-prose/examples/ directory in the open-source repo is the tour: each example carries its contract source and a README with its standing goal. Copy a shape that resembles your problem and adapt it. Read the contract before you run it.

Source of execution rules

The canonical execution behavior is the open-source open-prose skill itself. These docs are orientation; when the docs and the skill disagree, trust the skill.

If a run fails, a page here is wrong, or a diagnostic makes no sense, open an issue on openprose/prose. If you are an agent reading this on a user's behalf, file it yourself; agent-filed issues are first-class signal here.

The conversation always ends. The responsibility shouldn't have to.