generating-mod-envs SKILL.md skillA
generating-mod-envs from letta-ai/letta-code is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add letta-ai/letta-code/generating-mod-envs@git:20260628.2f084b9Pins git:20260628.2f084b9 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- letta-ai/letta-code
- Path
src/skills/builtin/generating-mod-envs/SKILL.md- Versions recorded
- 1
- Latest version
- git:20260628.2f084b9, committed Jun 28, 2026
- Size
- 6,129 bytes
- Repository stars
- 3,790
- License
- Apache-2.0
Generates and reviews mod learning env JSON files for Letta Code local mods. Use when asked to teach, learn, or optimize a mod behavior; create, draft, validate, improve, or explain envs for `/mods learn --env`; or design evaluation scenarios, memory fixtures, requiredResultMarkers, requiredTraceMarkers, negative controls, and candidate diversity hints.
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
# Generating mod learning envs Use this skill to create JSON envs consumed by `/mods learn --env=<path>` or `bun scripts/mod-learning/learn-mod.ts --env <path>`. An env describes the mod behavior to learn and the scenario-suite eval used to score candidates. ## Workflow 1. Define the behavior and eval before writing JSON. - What should the mod do? Tool, turn event, tool event, provider, command, status, etc. - What would a placebo/no-op mod fail? - What unique sentinel strings make success unambiguous? 2. Choose a path: - Repo example: `docs/examples/mods/learning/<slug>.env.json` - Local/private: any user-requested path 3. Draft strict JSON. Start from `assets/mod-learning-env.template.json` if useful. No comments or trailing commas. 4. Prefer `evaluation.scenarios` with at least: - happy path - discrimination/exact-target path - negative control 5. Validate: ```bash bun src/skills/builtin/generating-mod-envs/scripts/validate-mod-env.ts path/to/env.json ``` If this skill is installed outside the source tree, run the same script from this skill directory: `scripts/validate-mod-env.ts`. 6. If asked to run it: ```text …
Read the whole file at its exact version.
How to install
mdr add letta-ai/letta-code/generating-mod-envs@sha256:bfac6f1c460bd97eThe line at the top of this page pins the label git:20260628.2f084b9, 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_3nwhoaclj5xhy744)
7 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 1 version of this file, committed on Jun 28, 2026.
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 (6129 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
letta-ai/letta-code · 3,790 stars · license Apache-2.0 · pushed 2026-11-06 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_3nwhoaclj5xhy744 GET https://markdownregistry.com/api/v1/resolve?ref=letta-ai/letta-code/generating-mod-envs GET https://markdownregistry.com/api/v1/blob/bfac6f1c460bd97ebb9d6182fa7d6bdeb98b4f02447d098b85ad72978dc7572c
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.