feat(skill): add recsys-pipeline-architect

[mturac]

Adds a new community skill: recsys-pipeline-architect under skills/.

What this skill does

A spec-and-scaffold skill for designing composable recommendation, ranking, and feed pipelines using the six-stage Source → Hydrator → Filter → Scorer → Selector → SideEffect framework popularized by xAI's open-sourced For You algorithm (Apache 2.0). This skill is an independent reimplementation of the pattern (MIT) — no code copied from the original.

When invoked, it walks Copilot through eight clarifying steps (use case → sources → hydrations → filters → scorers → selector → side effects → scaffold), surfaces the architectural trade-offs you'd otherwise default through silently (multi-action vs single-score, candidate isolation vs joint, online vs offline batch), and produces a runnable scaffold in the user's stack.

Why it isn't covered by default model behavior

Per the What We Don't Accept → Duplicate Existing Model Strengths Without Meaningful Uplift guideline: this skill is not "tell Copilot to write generic TypeScript well." The six-stage framework, the multi-action vs single-score trade-off, and the candidate-isolation rule are domain-specific patterns from production recsys research. Frontier models without this skill consistently:

• Conflate scoring with selection (put sort inside the scorer)
• Suggest joint scoring as the default (non-deterministic, harder to cache)
• Default to a single relevance score even when the product wants multi-objective tuning
• Make side effects synchronous, blocking the response
• Skip filtering before scoring (waste compute)

The skill addresses these with hard rules and surfaces the trade-offs explicitly. The upstream repo has 5 reference docs that go deeper on each (interfaces in 4 languages, multi-action scoring, candidate isolation, filter cookbook, scorer cookbook).

PR contents

• Adds skills/recsys-pipeline-architect/SKILL.md (115 lines, single-file)
• Regenerates docs/README.skills.md via npm run build
• Ran npm run skill:validate → ✅ recsys-pipeline-architect is valid (and all 345 skills passed)
• Frontmatter follows the canonical fields: name, description, origin: community

Upstream

• Repository: https://github.com/mturac/recsys-pipeline-architect
• Release: v0.1.0 tagged
• Includes: SKILL.md + 5 reference docs + 3 runnable example scaffolds (Strapi v5/TS/Jest, Go with generics, Python/FastAPI/pytest — every one green: 9/9 tests passing total)
• License: MIT; attribution to the xAI pattern in upstream README and LICENSE
• Install via skills.sh (multi-agent): npx skills add mturac/recsys-pipeline-architect (also covers Cursor, Codex, Cline, Gemini CLI, OpenCode, and more)

Allow edits from maintainers: enabled. Happy to revise length, split into multiple skills, or move to a different category if you'd prefer.

[github-actions]

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[github-actions]

🔴 Contributor Reputation Check: HIGH risk

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