feat: add fastly-fiddle skill by acme · Pull Request #11 · fastly/fastly-agent-toolkit

acme · 2026-07-01T11:56:33Z

Add fastly-fiddle skill for testing VCL against real Fastly edge infrastructure via Fastly Fiddle
Include SKILL.md entrypoint plus references for the HTTP API, test DSL, spec shape, CI integration, and falco-vs-fiddle trade-offs
Add run-fiddle.sh helper (publish/execute/stream) and robots.json example spec
List fastly-fiddle in README available skills

- Add fastly-fiddle skill for testing VCL against real Fastly edge infrastructure via Fastly Fiddle - Include SKILL.md entrypoint plus references for the HTTP API, test DSL, spec shape, CI integration, and falco-vs-fiddle trade-offs - Add run-fiddle.sh helper (publish/execute/stream) and robots.json example spec - List fastly-fiddle in README available skills

- Add language tags to 13 unlabelled code fences (MD040) - Wrap 5 bare URLs in angle-bracket autolinks (MD034) - Align table columns and normalize formatting via Prettier (MD060)

- Convert the box-drawing flowchart in `falco-vs-fiddle.md` to a numbered list

- Replace `set var.used = a - b;` with compound assignment (`set var.used = a; set var.used -= b;`), which the current example got wrong - Note that Fastly VCL has no binary arithmetic operator in a `set`, a constraint independent of the parenthesized-concat rule

- Delete `references/ci-integration.md`; the Mocha/GitHub Actions boilerplate duplicated common knowledge - Add concise "Testing in CI" section to `SKILL.md` with the demo-fiddle-ci pointer and publish-once/re-execute-per-scenario fact - Drop the CI integration row from the references table

- Drop decision matrix from falco-vs-fiddle.md; core rows duplicated SKILL.md's "When Fiddle, when Falco" table - Preserve matrix-only context (falco is a Go reimplementation with compiler divergences) by folding it into the intro - Clarify division of labor: SKILL.md table for quick decision, reference for reasoning, workflow, and DSL differences

- Drop conventional-range table, historical-idiom prose, and stale meta-note from spec-shape.md - Keep actionable facts: 800–999 lint rejection, accepted range, `error 602` redirect pattern - Condense SKILL.md gotcha #7 and fix section anchor link

- GET's `valid` means "has executed", not "lints" — false for any un-executed fiddle - `--id` reuse wrongly bailed with exit 2; skip the check since lint ran at create - Breakage still surfaces via the existing "no results" (exit 4) path

- Distinguish `valid` semantics: compilation result on create/update vs execution status on `GET` - Warn that a `GET` cannot tell a valid-but-unrun fiddle from a broken one (both return `valid: false`, empty `lintStatus`) - Scope the lint-only error gate to create/update responses - Document that `GET /fiddle/:id` requires `Accept: application/json`, else it returns the HTML app

jedisct1 · 2026-07-03T17:21:44Z

Eval added, results are good, merging.

Thanks!

jedisct1 · 2026-07-03T17:36:30Z

task	none	fiddle	Δ	Fisher p
`fiddle-synthetic`	0/5 (0%)	5/5 (100%)	+100%	0.008
`fiddle-redirect`	0/5 (0%)	5/5 (100%)	+100%	0.008
`fiddle-cache-verify`	0/5 (0%)	4/5 (80%)	+80%	0.048
`fiddle-origin-header`	0/5 (0%)	3/5 (60%)	+60%	0.167
pooled	0/20 (0%)	17/20 (85%)	+85%	2.6e-08

Not perfect, but a massive improvement. Let's see what tweaks could be done to achieve a perfect score with the skills!

jedisct1 · 2026-07-03T18:22:14Z

Mostly fixed by ea3623d .

acme requested a review from jedisct1 July 1, 2026 11:56