docs: expand README with quickstart and tool docs

This commit is contained in:
David Ibia
2026-01-12 20:29:57 +01:00
parent 9c89528829
commit abe3467f37

224
README.md
View File

@@ -2,62 +2,9 @@
OpenCode plugin that prevents agents/tools from reading or editing sensitive `.env*` files, while still allowing safe inspection via EnvSitter (keys + deterministic fingerprints; never values). OpenCode plugin that prevents agents/tools from reading or editing sensitive `.env*` files, while still allowing safe inspection via EnvSitter (keys + deterministic fingerprints; never values).
## Why ## Quickstart (OpenCode)
Accidentally printing `.env` contents is one of the easiest ways for an agentic workflow to leak secrets into: OpenCode supports loading plugins from npm or local plugin files.
- chat transcripts
- logs/tool output
- commits/patches
- screenshots / shared sessions
`envsitter-guard` blocks the risky operations and points users to safe alternatives.
## What it does
This plugin does two things:
1. Adds safe tools:
- `envsitter_keys`: list keys in a dotenv file (no values)
- `envsitter_fingerprint`: hash/fingerprint one keys value (no value)
2. Blocks sensitive file access via OpenCode tool hooks:
- blocks `read` of sensitive `.env*` paths
- blocks `edit` / `write` / `patch` of sensitive `.env*` paths
- blocks access to `.envsitter/pepper`
`.env.example` is explicitly allowed.
## Tools
### `envsitter_keys`
Lists keys in a dotenv file.
- Input: `{ "filePath"?: string }` (defaults to `.env`)
- Output: JSON `{ file, keys }`
Example (inside OpenCode):
```json
{ "tool": "envsitter_keys", "args": { "filePath": ".env" } }
```
### `envsitter_fingerprint`
Computes a deterministic fingerprint of a single key.
- Input: `{ "filePath"?: string, "key": string }` (filePath defaults to `.env`)
- Output: JSON `{ file, key, result }`
Example (inside OpenCode):
```json
{ "tool": "envsitter_fingerprint", "args": { "filePath": ".env", "key": "DATABASE_URL" } }
```
## Install & enable in OpenCode
OpenCode supports loading plugins either from local files or from npm.
Reference docs: Reference docs:
- https://opencode.ai/docs/plugins/ - https://opencode.ai/docs/plugins/
@@ -76,6 +23,141 @@ Add the plugin package to your OpenCode config.
} }
``` ```
Restart OpenCode after updating config.
## Why
Accidentally printing `.env` contents is one of the easiest ways for an agentic workflow to leak secrets into:
- chat transcripts
- logs/tool output
- commits/patches
- screenshots / shared sessions
`envsitter-guard` blocks risky operations and points you to safe alternatives.
## What it does
This plugin provides safe EnvSitter-backed tools and blocks sensitive file access via OpenCode tool hooks.
### Safe tools (no values)
These tools never return raw `.env` values:
- `envsitter_keys`: list keys in a dotenv file
- `envsitter_fingerprint`: deterministic fingerprint of a single keys value
- `envsitter_match`: boolean/shape checks and outside-in candidate matching (without printing values)
- `envsitter_match_by_key`: bulk candidate-by-key matching (returns booleans only)
- `envsitter_scan`: scan value *shapes* (jwt/url/base64) without printing values
### Blocking behavior
- Sensitive paths: `.env`, `.env.local`, `.env.production`, etc. (`.env*`)
- Allowed: `.env.example`
- Always blocked: `.envsitter/pepper`
Blocked operations via tool hooks:
- `read` on sensitive `.env*` paths
- `edit` / `write` / `patch` / `multiedit` on sensitive `.env*` paths
When blocked, the plugin shows a throttled warning toast and suggests using EnvSitter tools instead.
## Tools
All tools accept a `filePath` that defaults to `.env`. Tools only operate on `.env`-style files inside the current project.
### `envsitter_keys`
Lists keys in a dotenv file.
- Input: `{ "filePath"?: string, "filterRegex"?: string }`
- Output: JSON `{ file, keys }`
Example (inside OpenCode):
```json
{ "tool": "envsitter_keys", "args": { "filePath": ".env" } }
```
Optional filtering:
```json
{ "tool": "envsitter_keys", "args": { "filePath": ".env", "filterRegex": "/^(API_|DB_)/" } }
```
### `envsitter_fingerprint`
Computes a deterministic fingerprint of a single key.
- Input: `{ "filePath"?: string, "key": string }`
- Output: JSON `{ file, key, result }`
Example (inside OpenCode):
```json
{ "tool": "envsitter_fingerprint", "args": { "filePath": ".env", "key": "DATABASE_URL" } }
```
### `envsitter_match`
Matches key values without printing them.
- Input:
- `{ "filePath"?: string, "op"?: string, "key"?: string, "keys"?: string[], "allKeys"?: boolean, "candidate"?: string, "candidateEnvVar"?: string }`
- Output:
- If `key` provided: JSON `{ file, key, op, match }`
- If `keys` or `allKeys`: JSON `{ file, op, matches }`
Notes:
- Provide exactly one selector: `key`, `keys`, or `allKeys: true`.
- For ops that compare against a candidate (`is_equal`, `partial_match_*`), provide `candidate` or `candidateEnvVar`.
Examples (inside OpenCode):
```json
{ "tool": "envsitter_match", "args": { "filePath": ".env", "key": "SENTRY_DSN", "op": "exists" } }
```
```json
{ "tool": "envsitter_match", "args": { "filePath": ".env", "key": "PORT", "op": "is_number" } }
```
```json
{ "tool": "envsitter_match", "args": { "filePath": ".env", "key": "NODE_ENV", "op": "is_equal", "candidate": "production" } }
```
### `envsitter_match_by_key`
Bulk match candidates-by-key without printing values (returns booleans only).
- Input:
- `{ "filePath"?: string, "candidatesByKey"?: Record<string,string>, "candidatesByKeyJson"?: string, "candidatesByKeyEnvVar"?: string }`
- Output: JSON `{ file, matches }`
Note: provide exactly one of `candidatesByKey`, `candidatesByKeyJson`, or `candidatesByKeyEnvVar`.
Example (inside OpenCode):
```json
{ "tool": "envsitter_match_by_key", "args": { "filePath": ".env", "candidatesByKey": { "NODE_ENV": "production" } } }
```
### `envsitter_scan`
Scan value shapes (jwt/url/base64) without printing values.
- Input: `{ "filePath"?: string, "detect"?: ("jwt"|"url"|"base64")[], "keysFilterRegex"?: string }`
- Output: JSON `{ file, findings }`
Example (inside OpenCode):
```json
{ "tool": "envsitter_scan", "args": { "filePath": ".env", "detect": ["jwt", "url"] } }
```
## Install & enable in OpenCode (alternatives)
### Option B: local plugin file (project-level) ### Option B: local plugin file (project-level)
@@ -106,21 +188,6 @@ Place a plugin file in `~/.config/opencode/plugin/` if you want it enabled for a
(You can use the same contents as Option B.) (You can use the same contents as Option B.)
## Behavior details
### What paths are considered sensitive?
- Sensitive: `.env`, `.env.local`, `.env.production`, etc. (`.env*`)
- Allowed: `.env.example`
- Always blocked: `.envsitter/pepper`
### What operations are blocked?
- `read` on sensitive `.env*` paths
- `edit` / `write` / `patch` on sensitive `.env*` paths
When blocked, the plugin shows a throttled warning toast and suggests using EnvSitter instead.
## Development ## Development
### Install ### Install
@@ -135,7 +202,22 @@ npm ci
npm run typecheck npm run typecheck
``` ```
There are currently no lint scripts in this repo. Run tests with `npm test`. ### Test
```bash
npm test
```
### Build (for publishing)
```bash
npm run build
```
## Notes
- This project intentionally avoids reading or printing `.env` values.
- EnvSitter CLI exists as an additional safe inspection option, for example: `npx envsitter keys --file .env`.
## License ## License