don-cheli-sdd: Skill for Claude Code

.agent/skills/doncheli-distill/SKILL.md

doncheli-distill is a skill for Claude Code from doncheli/don-cheli-sdd. It costs 56 tokens per session (416 once invoked), scanned A, original, Apache-2.0.

A reverse-engineering skill that turns existing code into a plain-language specification and architecture diagram. It describes observed behavior, data flows, rules, edge cases, and unclear areas.

In plain words
What is it for?
Documenting services or modules, tracing inputs to outputs, writing behavior scenarios in Gherkin, and mapping system architecture.
Why use it?
It helps developers understand an unfamiliar codebase without relying only on its implementation details.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

This is doncheli/don-cheli-sdd's own configuration. It tells Claude Code how to work on don-cheli-sdd itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything don-cheli-sdd configures →

Part of the don-cheli-sdd plugin — 28 skills, 115 commands, 1 agent shipped together

Reuse

Borrowing it

Nothing to install: this file belongs to doncheli/don-cheli-sdd. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/doncheli/don-cheli-sdd/main/.agent/skills/doncheli-distill/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/doncheli/don-cheli-sdd

Made for: Claude Code.

Or install don-cheli-sdd, the plugin that ships this one along with the rest of its 28 skills, 115 commands, 1 agent.

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 doncheli-distill

README.md
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Your own site
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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.

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Your own site · 80×15
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Per session 56 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 416 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. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 $0.00056 $0.00416
Opus 5 $0.00028 $0.00208
Sonnet 5 $0.00011 $0.00083
Haiku 4.5 $0.00006 $0.00042

Measured 12d ago against content hash 06c736cc6285, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

doncheli-distill 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 12d 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.

.agent/skills/doncheli-distill/SKILL.md · 62 lines

What it actually says

Don Cheli: Blueprint Distillation

Instructions

  1. Identify the target module, service or codebase to distill
  2. Scan entry points (routes, controllers, event handlers, CLI commands)
  3. Trace data flows: inputs → transformations → outputs → side effects
  4. Identify implicit business rules embedded in conditionals, validations, error handling
  5. Map entity relationships from data models and DB schemas
  6. Generate Gherkin scenarios that describe the observed behavior (not the code)
  7. Produce a C4-style architecture diagram in text (Mermaid or ASCII)
  8. Flag ambiguities, dead code, and undocumented assumptions with [NEEDS CLARIFICATION]

Output Format

## Blueprint: <module/service name>

### Architecture Diagram
```mermaid
…

Distilled Spec (Gherkin)

Feature: <name>
  Background: …

  Scenario: <happy path>
    Given …
    When …
    Then …

  Scenario: <edge case / sad path>
    …

Implicit Business Rules

  1. — found in: file:line

Ambiguities & Dead Code


## Quality Gate

- Every entry point must map to at least one Gherkin scenario
- Architecture diagram must show at least: external inputs, internal modules, data stores, external services
- Business rules must cite their source location

## Do not use this skill when

- The user wants to write new specs for a new feature (use doncheli-spec instead)
- The codebase has no existing logic to analyze
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. 12d ago First seen · 62 lines · 56 tokens per session scan A 06c736cc6285

Subscribe to this mod's changes

doncheli-distill is a skill published in the GitHub repository doncheli/don-cheli-sdd (57 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 56 tokens to every session and 416 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.