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jsvillalbatjsvillalbat/sevito-skills/skills/metaprompt/SKILL.md

metaprompt

Skill0 starsChanged 3 months agoMITView on GitHub

Given a goal, a target model, and a target harness, produces a complete, ready-to-use prompt engineered for that specific combination — researching current per-model and per-harness prompting techniques rather than relying on stale memorized guidance, then self-reviewing the draft against a quality checklist. Use when writing a prompt, system message, or agent instructions meant to run on a specific model (Claude, GPT-5.x, Gemini, etc.) inside a specific harness (Claude Code, Codex CLI, a custom agent loop, raw API, chat) — especially one that isn't the model/harness currently running this conversation.

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    1. JairoTorregrosa/jaiskills★ 11same name

    How matches are found. Word for word: the exact same text. Edited: shares passages with this file (“99% same” means 99% of its five-word phrases also appear here; 10% or more counts). Their own version: similar meaning, or, weakest, the same name. We can’t tell which project had it first. Projects are counted among the 200 most-starred candidates, and mentions are links to the repository we found, up to 50 per site, so both counts are a floor.

  • In this repository8 other files it gives its agents.

The file

We split this skill into the rules it gives an agent

4 rules. About 0 are common, 4 are distinctive, and 0 are very specific to this project.

  • ≈0

    Common · estimate

    Many files like this have a rule of this kind.

  • ≈4

    Distinctive · estimate

    This author's own choices. Worth a look.

  • 0

    Very specific

    Tied to their project's names, files or tools. Probably skip.

  • Common
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  1. Distinctive:

    If any is missing or ambiguous, ask before drafting — a prompt optimized for the wrong model/harness combination isn't a safe default to …

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  2. Distinctive:

    Look up the target model's current official prompting guidance (WebSearch/ WebFetch its vendor's docs).

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  3. Distinctive:

    Look up the target harness's own conventions and docs (a harness-specific instructions-file format, its tool-calling conventions, what …

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  4. Distinctive:

    Treat anything you already "know" about a model's quirks as a hypothesis to verify, not a fact to assert — this is exactly the staleness …

    line 53

≈ “Common” is an estimate: at least 1 in 5 of the 350,495 skill files we read have a rule of the same kind, not the same words. “Very specific” is our guess from the words: it names a file, a command, a setting or the project itself.

Keep what fits and drop the rest. Your version, ready for your agents.
Files
SKILL.md

Metaprompt

A prompt written by feel, without checking what actually works for the specific model and harness that will run it, tends to either under-specify (missing a technique that model responds well to) or over-specify (re-stating things the harness already guarantees, which dilutes attention). This skill treats prompt-writing as a small research task with three required inputs, not a one-shot creative exercise.

When to use this

  • Writing a prompt, system message, or agent instructions meant to run on a specific model inside a specific harness — most valuably when that combination differs from the one currently running this conversation (you can't rely on your own default behavior as a stand-in for how the target will behave).
  • The user asks to "write a prompt for X model" or "write the system prompt for this agent" and names or implies a target model/harness.

Instructions

1. Get all three required inputs

  • Goal — what should the resulting prompt make the model do?
  • Target model — the specific model/family (e.g. "Claude Opus 4.8," "GPT-5.2," "Gemini 3 Pro"). Techniques differ meaningfully even within one vendor's lineup — don't accept "an LLM" as an answer.
  • Target harness — what will actually run this prompt: Claude Code, Codex CLI, a custom agent loop, the raw API, a chat UI, something else. This determines what the harness already handles for you vs. what the prompt must spell out.

If any is missing or ambiguous, ask before drafting — a prompt optimized for the wrong model/harness combination isn't a safe default to fall back on.

2. Research before writing — don't rely on memorized specifics

Model and harness idioms change as often as the models themselves ship. Before drafting:

  • Look up the target model's current official prompting guidance (WebSearch/ WebFetch its vendor's docs). If a skill already available in this environment is specifically authoritative for that model/vendor (for example this repo's own claude-api skill for Claude/Anthropic), prefer it over general web search.
  • Look up the target harness's own conventions and docs (a harness-specific instructions-file format, its tool-calling conventions, what context it injects automatically).
  • Treat anything you already "know" about a model's quirks as a hypothesis to verify, not a fact to assert — this is exactly the staleness this skill exists to avoid.

references/research-checklist.md lists the categories to investigate for the model and the harness — deliberately not a list of hardcoded facts, since those go stale.

3. Apply what you found

  • Model-specific: structuring conventions the model responds to (XML tags, markdown, JSON), how it handles extended/visible reasoning, how literally it follows instructions, anything relevant to the goal around refusals/safety framing.
  • Harness-specific: what the harness already provides automatically (tool definitions, cwd/git context, sandboxing, available tools) — don't re-specify it, that's redundant and dilutes the prompt. What output format the harness expects and parses. Where the harness's own extension points are (system prompt vs. user message vs. a dedicated config/instructions file).

The harness guide is the authority on what to omit, not just what to add.

4. Assemble, then self-review before delivering

Draft the complete prompt, then check it against:

  • Is the goal unambiguous to someone with zero other context?
  • Are format instructions precise and actually match what the harness parses?
  • Does it redundantly restate anything the harness already guarantees?
  • Any internal contradictions between sections?
  • Is it as concise as the goal allows — a bloated prompt degrades attention as much as a vague one does?

Full checklist in references/research-checklist.md.

5. Deliver three things

  1. The ready-to-paste prompt, in a code block.
  2. Parameter recommendations if applicable (reasoning/thinking effort, temperature, and similar) for the target model.
  3. One sentence naming the key model- or harness-specific technique that shaped this prompt — so the user understands why it's written this way, not just what to paste.

Reference files

  • references/research-checklist.md — what to look up per model and per harness, and the pre-delivery self-review checklist.

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