ml4t-agent-tool-contracts SKILL.md skillA
ml4t-agent-tool-contracts from ml4t/skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add ml4t/skills/ml4t-agent-tool-contracts@git:20260901.c415df0Pins git:20260901.c415df0 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- ml4t/skills
- Path
advanced-ai/agent-tool-contracts/SKILL.md- Versions recorded
- 2
- Latest version
- git:20260901.c415df0, committed Sep 1, 2026
- First version recorded
- May 28, 2026
- Size
- 3,346 bytes
- Repository stars
- 41
- License
- Apache-2.0
Typed tool contracts for autonomous research agents. Use when exposing files, search, databases, or execution tools to an LLM agent.
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
# Agent Tool Contracts
An agent tool is an API boundary, not a prompt convenience. Every tool needs a typed input schema, a narrow execution policy, and a result object that records provenance.
## The Problem
LLM agents fail badly when tools accept vague strings and return unstructured text. The model cannot distinguish stale search results from fresh ones, allowed paths from forbidden paths, or recoverable tool errors from final evidence. Worse, a prompt-injected page can ask the agent to call another tool unless the execution layer enforces policy outside the model.
## The Pattern
### WRONG
```python
def run_tool(name: str, args: str) -> str:
if name == "read_file":
return open(args).read()
if name == "search":
return web_search(args)
raise ValueError(name)
```
### CORRECT
```python
from dataclasses import dataclass
from pathlib import Path
from typing import Any
@dataclass(frozen=True)
class ToolResult:
ok: bool
value: Any
source: str
observed_at: str
policy: str
def read_file(path: str, root: Path) -> ToolResult:
requested = Path(path).expanduser().resolve()
allowed = root.resolve()
…Read the whole file at its exact version.
How to install
mdr add ml4t/skills/ml4t-agent-tool-contracts@sha256:31952cae1e6e0acdThe line at the top of this page pins the label git:20260901.c415df0, 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_ois75sdbcmoxikd4)
2 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 2 versions of this file, between May 28, 2026 and Sep 1, 2026, about one every 96 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260901.c415df0 latest | 2026-09-01 | c415df0 | 3,346 B | A | view · diff |
| git:20260528.303089e | 2026-05-28 | 303089e | 3,359 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (3346 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
ml4t/skills · 41 stars · license Apache-2.0 · pushed 2026-11-08 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_ois75sdbcmoxikd4 GET https://markdownregistry.com/api/v1/resolve?ref=ml4t/skills/ml4t-agent-tool-contracts GET https://markdownregistry.com/api/v1/blob/31952cae1e6e0acdcc722ce144b91296622e23fa2a0a8f14a172643ce3fa5c53
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: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.