fsl SKILL.md skillA
fsl from ymm-oss/fsl is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add ymm-oss/fsl/fsl@git:20261107.deab533Pins git:20261107.deab533 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- ymm-oss/fsl
- Path
skills/fsl/SKILL.md- Versions recorded
- 14
- Latest version
- git:20261107.deab533, committed Nov 7, 2026
- First version recorded
- Aug 9, 2026
- Size
- 25,406 bytes
- Repository stars
- 37
- License
- Apache-2.0
Shared FSL language and verifier reference for writing, checking, verifying, repairing, explaining, mutating, refining, replaying, generating scenarios/test scaffolds, and interpreting fslc JSON results. Use directly for FSL syntax, kernel specs, verifier errors, repair loops, and command usage. For role-specific authoring, prefer fsl-business for business flows, fsl-requirements for PM requirements/acceptance/NFR specs, and fsl-design for engineering design/refinement work; for choosing the…
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
# FSL Core — Language, Verifier, and Repair Loop FSL is a language not present in training data. **Do not write from memory; follow this guide.** Use the reference index below to read only the topical material needed for the task. **What makes FSL different — connectivity, not just per-spec checking.** Classic formal methods describe one hard spot and verify it in isolation (the "island" model). FSL's distinctive value is stitching business ⊒ requirements ⊒ design together with refinement, so **cross-layer alignment (traceability) is itself checkable** — the dominant question moves from "is this spec correct?" to "do these layers still mean the same thing?" Verify a one-off hard spot with a single spec; when the value is keeping the layers aligned, reach for the connected workflow (`fslc chain`) and the `fsl-delivery` skill. The two workflows are juxtaposed below. ## Editions: FSL 4 and FSL 5 The header selects the syntax. A document whose first non-trivia line is `fsl 5` (blank lines and `//` comments may precede it; document annotations and the dialect keyword follow it) is FSL 5. **A headerless document is FSL 4**, as …
Read the whole file at its exact version.
How to install
mdr add ymm-oss/fsl/fsl@sha256:d02c695e3eface10The line at the top of this page pins the label git:20261107.deab533, 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_rapdtj32dafe2j5e)
4 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 14 versions of this file, between Aug 9, 2026 and Nov 7, 2026, about one every 7 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20261107.deab533 latest | 2026-11-07 | deab533 | 25,406 B | A | view · diff |
| git:20261026.5a08593 | 2026-10-26 | 5a08593 | 22,876 B | A | view · diff |
| git:20261019.9dc515e | 2026-10-19 | 9dc515e | 21,887 B | A | view · diff |
| git:20261017.bf06ebf | 2026-10-17 | bf06ebf | 21,917 B | A | view · diff |
| git:20261017.c62f013 | 2026-10-17 | c62f013 | 21,767 B | A | view · diff |
| git:20261015.67464a1 | 2026-10-15 | 67464a1 | 21,741 B | A | view · diff |
| git:20261001.bd4cc94 | 2026-10-01 | bd4cc94 | 21,345 B | A | view · diff |
| git:20260929.d8a8acc | 2026-09-29 | d8a8acc | 21,256 B | A | view · diff |
| git:20260924.22b8071 | 2026-09-24 | 22b8071 | 21,221 B | A | view · diff |
| git:20260915.d7893bb | 2026-09-15 | d7893bb | 21,199 B | A | view · diff |
| git:20260911.246f098 | 2026-09-11 | 246f098 | 20,952 B | A | view · diff |
| git:20260907.dbbf688 | 2026-09-07 | dbbf688 | 19,736 B | A | view · diff |
| git:20260828.927728f | 2026-08-28 | 927728f | 19,466 B | A | view · diff |
| git:20260809.60705fd | 2026-08-09 | 60705fd | 54,948 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 (25406 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
ymm-oss/fsl · 37 stars · license Apache-2.0 · pushed 2026-11-07 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_rapdtj32dafe2j5e GET https://markdownregistry.com/api/v1/resolve?ref=ymm-oss/fsl/fsl GET https://markdownregistry.com/api/v1/blob/d02c695e3eface10635d4983694946ba81f6753920a5cfee3e3ef0e600fd9e74
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.