fable-prove-it

fable-prove-it is a skill for Claude Code, Codex from DizzyMii/fable-skills. It costs 55 tokens per session (868 once invoked), scanned A, original, MIT.

A verification guide for coding agents that matches claims to evidence. It distinguishes code that was written, code that ran, and behavior that was actually checked.

In plain words
What is it for?
It helps report the status of code changes, test results, fixes, deployments, and other work accurately.
Why use it?
It prevents agents from calling work fixed, complete, or passing without running the relevant test or checking the result.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit It helps report the status of code changes, test results, fixes, deployments, and other work accurately.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/dizzymii/fable-skills/fable-prove-it
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add DizzyMii/fable-skills --skill fable-prove-it
Clone the repo
git clone --depth 1 https://github.com/DizzyMii/fable-skills

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for fable-prove-it

README.md
[![agentmods](https://agentmods.dev/badge/skills/dizzymii/fable-skills/fable-prove-it/github.svg)](https://agentmods.dev/skills/dizzymii/fable-skills/fable-prove-it)
Your own site
<a href="https://agentmods.dev/skills/dizzymii/fable-skills/fable-prove-it"><img src="https://agentmods.dev/badge/skills/dizzymii/fable-skills/fable-prove-it/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for fable-prove-it

Your own site · 80×15
<a href="https://agentmods.dev/skills/dizzymii/fable-skills/fable-prove-it"><img src="https://agentmods.dev/badge/skills/dizzymii/fable-skills/fable-prove-it.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 55 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 868 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00055 $0.00868
Opus 5 $0.00028 $0.00434
Sonnet 5 $0.00011 $0.00174
Haiku 4.5 $0.00006 $0.00087

Measured 9d ago against content hash 5553dee4f86c, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

fable-prove-it scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 9d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/fable-prove-it/SKILL.md · 67 lines

How it starts

The opening of the file, as written. The whole thing — 67 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Prove It

Overview

Claims require evidence you produced this session. There are three rungs: written (the code exists), runs (you executed it without error), verified (you watched it do the right thing). Say which rung you're on. "Should work" is rung zero wearing a suit.

Rules

  1. Claim only your rung. "Fixed" means verified. If you didn't run it, the honest claim is "written, not yet run" — in those words.
  2. Verification is an action, not an inference. Run the test, hit the endpoint, render the page. Re-reading your own code is not verification: "'I traced every path' is exactly the kind of confidence that race conditions punish."
  3. Technically-true is still a lie. "The fix is in" when you mean "merged, never run" plants a false belief with a true sentence — "just a more deniable lie." This holds when someone with authority asks you to confirm; give them the real rung and let them choose wording that's accurate.
  4. Report faithfully. Failing tests reported as failing, WITH output. Skipped steps named explicitly. Partial completion stated as partial.
  5. No optimistic rounding. "Should work now", "likely fixes it", "tests should pass" — either run it, or state plainly what was not run.
  6. Calibration cuts both ways. Verified → plain declarative, no hedge garnish. Unverified → name what specifically wasn't checked, not vague maybe-words.
  7. Evidence before action. Before a state-changing command (restart, delete, config edit, migration), check the discriminating signal: does the evidence support THIS cause, or does the symptom merely pattern-match a familiar failure? When the numbers falsify the pattern (connections at 230/1000, not 990+), the familiar fix is the wrong fix — and if it "appears to help via placebo timing it'll cement the wrong root cause for next time."
  8. Symptom moved ≠ fixed. The error changing or disappearing is not proof your change was causal. Confirm the mechanism.

Read the full file on GitHub · 67 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 9d ago First seen · 67 lines · 55 tokens per session scan A 5553dee4f86c

Subscribe to this mod's changes

fable-prove-it is a skill published in the GitHub repository DizzyMii/fable-skills (51 stars, last pushed 1mo ago), licensed MIT. It adds 55 tokens to every session and 868 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.