AGENTS.mdA
AGENTS.md from pydantic/pydantic-ai-harness is an AGENTS.md file: the standing instructions coding agents read in that repo.
mdr add pydantic/pydantic-ai-harness/AGENTS.md@git:20260918.f6f02e6Pins git:20260918.f6f02e6 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 14 of 14 checks passed
- Kind
- AGENTS.md file
- Repository
- pydantic/pydantic-ai-harness
- Path
AGENTS.md- Versions recorded
- 6
- Latest version
- git:20260918.f6f02e6, committed Sep 18, 2026
- First version recorded
- Jul 28, 2026
- Size
- 13,192 bytes
- Repository stars
- 960
- License
- MIT
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Pydantic AI Harness ## Repository purpose `pydantic-ai-harness` is the first-party capability library for Pydantic AI. Pydantic AI core owns the primitive runtime: agent loop semantics, normalized messages, model/provider/profile behavior, tool execution semantics, durable execution primitives, and generic capability hooks. Harness owns optional, batteries-included compositions built from those primitives: coding-agent tools, guardrails, memory, context management, repo tools, verification loops, skills, planning, sub-agents, and other reusable agent behaviors. When a change needs new core semantics, stop and propose the Pydantic AI core change instead of reimplementing core behavior in harness. ## Vocabulary - **Capability**: an `AbstractCapability` subclass that bundles tools, hooks, instructions, and model settings into a reusable unit. This is the core abstraction of pydantic-ai-harness. - **Hook**: a lifecycle method on `AbstractCapability` that intercepts agent graph execution (e.g. `before_model_request`, `wrap_run`, `after_tool_execute`) - **Toolset**: a collection of tools that a capability can provide to the agent …
Read the whole file at its exact version.
How to install
mdr add pydantic/pydantic-ai-harness/AGENTS.md@sha256:5dddc346b2a0672dThe line at the top of this page pins the label git:20260918.f6f02e6, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_pr3t73iajamnfoey)
2 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 6 versions of this file, between Jul 28, 2026 and Sep 18, 2026, about one every 10 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260918.f6f02e6 latest | 2026-09-18 | f6f02e6 | 13,192 B | A | view · diff |
| git:20260909.74a3d4a | 2026-09-09 | 74a3d4a | 12,105 B | A | view · diff |
| git:20260908.f6c64d4 | 2026-09-08 | f6c64d4 | 11,738 B | A | view · diff |
| git:20260822.643f664 | 2026-08-22 | 643f664 | 11,167 B | A | view · diff |
| git:20260804.d7e30e9 | 2026-08-04 | d7e30e9 | 10,717 B | A | view · diff |
| git:20260728.70c4b6c | 2026-07-28 | 70c4b6c | 10,265 B | A | view |
Audit of the latest version
- pass: Size between 200 bytes and 200 KB (13192 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
pydantic/pydantic-ai-harness · 960 stars · license MIT · pushed 2026-10-02 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_pr3t73iajamnfoey GET https://markdownregistry.com/api/v1/resolve?ref=pydantic/pydantic-ai-harness/AGENTS.md GET https://markdownregistry.com/api/v1/blob/5dddc346b2a0672d65685cee6cedd1fcd51a15eff677392c5d72bfe921be7fe4
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: how to write a good AGENTS.md · AGENTS.md vs CLAUDE.md · which agent file does what.
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