core-agent-ide/codex-rs/execpolicy/README.md
zhao-oai fe7a3f0c2b
execpolicycheck command in codex cli (#7012)
adding execpolicycheck tool onto codex cli

this is useful for validating policies (can be multiple) against
commands.

it will also surface errors in policy syntax:
<img width="1150" height="281" alt="Screenshot 2025-11-19 at 12 46
21 PM"
src="https://github.com/user-attachments/assets/8f99b403-564c-4172-acc9-6574a8d13dc3"
/>

this PR also changes output format when there's no match in the CLI.
instead of returning the raw string `noMatch`, we return
`{"noMatch":{}}`

this PR is a rewrite of: https://github.com/openai/codex/pull/6932 (due
to the numerous merge conflicts present in the original PR)

---------

Co-authored-by: Michael Bolin <mbolin@openai.com>
2025-11-20 16:44:31 -05:00

62 lines
2.4 KiB
Markdown

# codex-execpolicy
## Overview
- Policy engine and CLI built around `prefix_rule(pattern=[...], decision?, match?, not_match?)`.
- This release covers the prefix-rule subset of the execpolicy language; a richer language will follow.
- Tokens are matched in order; any `pattern` element may be a list to denote alternatives. `decision` defaults to `allow`; valid values: `allow`, `prompt`, `forbidden`.
- `match` / `not_match` supply example invocations that are validated at load time (think of them as unit tests); examples can be token arrays or strings (strings are tokenized with `shlex`).
- The CLI always prints the JSON serialization of the evaluation result.
- The legacy rule matcher lives in `codex-execpolicy-legacy`.
## Policy shapes
- Prefix rules use Starlark syntax:
```starlark
prefix_rule(
pattern = ["cmd", ["alt1", "alt2"]], # ordered tokens; list entries denote alternatives
decision = "prompt", # allow | prompt | forbidden; defaults to allow
match = [["cmd", "alt1"], "cmd alt2"], # examples that must match this rule
not_match = [["cmd", "oops"], "cmd alt3"], # examples that must not match this rule
)
```
## CLI
- From the Codex CLI, run `codex execpolicy check` subcommand with one or more policy files (for example `src/default.codexpolicy`) to check a command:
```bash
codex execpolicy check --policy path/to/policy.codexpolicy git status
```
- Pass multiple `--policy` flags to merge rules, evaluated in the order provided, and use `--pretty` for formatted JSON.
- You can also run the standalone dev binary directly during development:
```bash
cargo run -p codex-execpolicy -- check --policy path/to/policy.codexpolicy git status
```
- Example outcomes:
- Match: `{"match": { ... "decision": "allow" ... }}`
- No match: `{"noMatch": {}}`
## Response shapes
- Match:
```json
{
"match": {
"decision": "allow|prompt|forbidden",
"matchedRules": [
{
"prefixRuleMatch": {
"matchedPrefix": ["<token>", "..."],
"decision": "allow|prompt|forbidden"
}
}
]
}
}
```
- No match:
```json
{"noMatch": {}}
```
- `matchedRules` lists every rule whose prefix matched the command; `matchedPrefix` is the exact prefix that matched.
- The effective `decision` is the strictest severity across all matches (`forbidden` > `prompt` > `allow`).
Note: `execpolicy` commands are still in preview. The API may have breaking changes in the future.