Invocation for
vc-skillaunch(foundation skill)Not a core
vibecrafted skillaunch <agent>worker. Load interactively and execute in-session. Package other skills under the Delegation Matrix — per-launcher literals, no workflow paste, freer native when packaging needs depth, external fleet unchanged. See Foundation skills.
Workflow-to-Skill Distiller
Turns a completed workflow into a reusable agent skill. Specifically, this skill extracts patterns from an interaction or workflow that already happened and packages them.
Canonical Orientation Gate
If the workflow being distilled depends on a repository, run or consume the
vc-init procedure before writing the skill contract. Loctree:loctree is the
default structural perception skill for that pass and must produce or refresh
the Code-Derived Application Map.
If fresh vc-init evidence is absent, perform the init pass first and treat
repo-dependent skill writing as blocked until repo truth exists.
If the workflow is not repo-specific, state the no-repo exception and distill the interaction evidence directly.
[!CAUTION] You MUST complete Phase 1 (Brainstorming) before writing any code or SKILL.md content. Skipping brainstorming produces skills that are either too rigid or too vague. The brainstorming conversation is the most important part of this process.
Repository Work Doctrine
For repository work, start with Loctree as the map: use loct context,
loct occurrences, loct body, and loct find --literal before broad manual
search. Use AICX for intent and session context. Use rg/grep as fallback or
local magnifier, not as a replacement for structural mapping. If Loctree fails
or misses a surface, append feedback to ~/.vibecrafted/loctree/loctree-fail.md.
Phase 1: Brainstorming (MANDATORY)
Have an iterative back-and-forth conversation with the user. Do NOT ask all questions at once. Pick 2-3 relevant questions per round from the bank below, refine your understanding, and ask follow-ups.
Round 1: Understand the Workflow
Start by summarizing what you observed from the workflow, then ask:
- "Here's my understanding of the workflow: [summary]. Is this accurate? What would you change?"
- "What are the expected inputs and outputs for this workflow?"
- "How often do you expect to run this workflow? Is it recurring or one-off?"
Round 2: Flexibility and Error Handling
For each step identified in the workflow, determine its rigidity:
- "For [step X], if the primary approach fails (e.g., API down, no results), should the agent: (a) ask you for guidance, (b) try alternative approaches automatically, or (c) fail loudly with an error?"
- "Are there any steps where the exact method matters (e.g., must use a specific database), vs. steps where any reasonable approach is fine?"
- "Should the skill handle edge cases silently or surface them to the user?"
Round 3: Dependencies and Resources
Before asking these questions, check which of your installed skills overlap with the workflow. If an existing skill from the science bundle covers a step, the new skill MUST reference it — do not offer a self-contained option.
- "I noticed the workflow uses functionality covered by [existing skill X, skill Y]. The new skill will reference these rather than reimplementing them. Are there any other tools or skills you'd like me to incorporate?"
- "Are there any API rate limits I should be aware of for services used in this workflow that aren't already covered by an existing skill?"
- "Are there specific files that provide important scientific context for creating this skill? For example: API documentation, reference papers, example datasets, or domain-specific notes. If so, please share them and I will incorporate their content into the skill's reference materials."
Round 4: Scope, Shape, and Matrix Class
- "Our workflow covered [X, Y, Z]. Should I distill all of these into the skill, or is there additional functionality that's important to include? Conversely, should any of these be left out?"
- Delegation Matrix class — decide before naming the launcher:
- Core launcher — will ship as
vibecrafted <name> <agent>//vc-<name> - Meta — init / ship / dispatch / operator-style surface
- Foundation — no worker CLI; loaded inside other skills
Confirm the class and the exact literals with the user. Never invent
vibecrafted <workflow> <agent>as a universal placeholder. ReadDELEGATION_MATRIX.md.
- Core launcher — will ship as
- Determine whether the skill needs any code. If any step involves calling an
API, processing data, reading/writing files, or computing results, the skill
needs code and you should default to the CLI pattern. Only use a
text-only instruction skill when every step is purely about reasoning,
coordinating existing tools, or following a written protocol with no
programmatic work at all. Confirm your assessment with the user in plain
language:
- If code is needed: "Some of these steps involve [fetching data from an
API / processing files / computing results], so I'll create a helper
script that the agent can run for you. The script will have simple
commands like
search,fetch,analyze, etc. — you won't need to write any code yourself. Does that sound right?" - If no code is needed: "This workflow is entirely about following a set of steps and using existing tools — no new code is needed. I'll write it as a set of clear instructions the agent follows. Does that sound right?"
- If code is needed: "Some of these steps involve [fetching data from an
API / processing files / computing results], so I'll create a helper
script that the agent can run for you. The script will have simple
commands like
- If a helper script will be created: "I'm thinking the script should have these commands: [proposed commands in plain English, e.g. 'search for proteins', 'fetch results', 'compare sequences']. What would you add or change?"
- "What should the skill be called? Proposed name:
[suggestion]." If core launcher: proposed CLIvibecrafted <launcher> <agent>must match.
Round 5: Testing (Optional)
- "Can you provide a sample query and expected answer that I can use to verify the skill works as intended? For example: 'If I ask [question], the skill should produce [answer].' This is optional but helps me validate the skill during development."
Brainstorming Completion Criteria
You are ready to move to Phase 2 when you can confidently answer ALL of:
- What is the workflow's purpose and scope?
- What are the inputs and outputs?
- Which steps are strict vs. flexible?
- Which existing skills should be referenced?
- What new scripts (if any) are needed?
- What rate limits apply?
- How should errors be handled?
- Does the workflow need any code? (If yes → CLI pattern; if no → instruction-only)
- Matrix class (core launcher / meta / foundation) and exact literals?
- Is there a sample query/answer for validation?
Phase 2: Skill Design
Produce a design document (as an artifact / implementation plan) and present it to the user for approval. The document must include:
- Skill name and description (following YAML frontmatter rules: name ≤64 chars, lowercase + hyphens; description ≤1024 chars; third-person triggers).
- Matrix class + invocation table (worker / interactive / operator) with concrete literals for this skill only.
- Directory structure showing all planned files (prefer progressive
disclosure: lean SKILL.md, detail in
references/). - Existing skills referenced with rationale for each.
- New scripts (if any) with proposed subcommands and arguments.
- Rate limiting strategy for any APIs not covered by existing skills.
- Error handling strategy per step.
Wait for explicit user approval before proceeding to Phase 3.
Phase 3: Implementation
Guiding Principles
General guidelines for skill implementation:
- Use
uv run, neverpythonorpython3. - Prefer stdlib libraries that come with a default Python 3 installation
(
urllibpreferred); Avoid libraries that require extra installation if possible. - Rate limits must be documented and respected in code. Prefer file-lock–based rate limiting so that concurrent sub-agents sharing the same machine collectively respect the limit. See other skills in the Science Skills bundle for the canonical cross-process–safe implementation.
- Skill output must be <500 lines or redirected to a file. Long output files should be processed programmatically to extract relevant fields.
- Hyphens are recommended for the skill name and YAML
name:field.
Rule 1: Reuse Existing Skills
When the workflow uses functionality covered by an existing installed skill, the new SKILL.md MUST reference it by name rather than reimplementing. Include a Dependencies section in the SKILL.md listing required skills with a brief rationale for each.
Rule 2: Rate Limiting for New APIs
For any API interaction not covered by an existing skill, the generated CLI
script MUST implement rate limiting. Before writing any rate-limiting code,
look up the API's official rate-limit guidelines: check any documentation
the user provided during brainstorming, then search the API's public
documentation online. If no documented rate limit can be found, default to 1
request per second. The rate limiting pattern is built directly into the CLI
template at references/cli_script_template.py — see the RateLimitError class
and the _request method of the API client.
Key requirements:
- Use
time.monotonic()for timing (nottime.time()). - Calculate delay from documented rate limits.
- Implement retry with exponential backoff for transient errors (5xx).
- Raise a dedicated
RateLimitErrorwhen HTTP 429 is received. - Log retry attempts to stderr so the agent can observe progress.
- Include the URL and rate-limit value in error messages.
- On non-retriable HTTP errors (e.g. 400, 403, 404), read and include the response body in the error message — not just the status code. API response bodies contain actionable details (e.g., "Invalid parameter") that enable the agent to self-correct.
Rule 3: CLI Script Pattern (Default When Code Is Needed)
This is the default choice. If any step in the workflow involves API
calls, data processing, file I/O, computation, or any other programmatic work,
produce a multi-command CLI script using argparse with subcommands. Follow the
template in references/cli_script_template.py.
Key requirements:
- Each major workflow step becomes a subcommand.
- All subcommands accept
--outputfor writing results to a file. - Use
json.dumpwithindent=2for JSON output. - Print a success message with the output file path.
- Exit with code 1 on errors.
- Make arguments like
--limitrequired (no silent defaults). This forces the agent to specify the value explicitly, preventing it from assuming it retrieved "all" results when it was silently capped.
Rule 4: Default to File Output
All scripts and workflows MUST write output to files, not stdout. Stdout should only contain short status messages (e.g., "Success! Data written to: results.json"). This is critical because:
- API responses can be very large and will truncate in terminal output.
- File output is token-efficient — the agent reads only the fields it needs
using
jpor Python one-liners. - Large stdout output wastes context window space.
Rule 5: Instruction-Only Pattern (Only When No Code Is Needed)
Use this pattern only when the workflow requires zero programmatic work — i.e., every step is purely about orchestration, reasoning, multi-skill coordination, or following a written protocol. If any step needs code (API calls, data processing, file I/O, etc.), use the CLI pattern from Rule 3 instead. Produce a SKILL.md with a structured workflow section:
## Workflow
### 1. Step Name
- Description of what to do
- Which skill to use and how
### 2. Next Step
...
Rule 6: SKILL.md Structure
Every generated SKILL.md must follow this structure (imperative body language;
third-person description with concrete triggers):
---
name: { skill-name }
description: >-
This skill should be used when the user asks to "…", "…". {outcome}.
version: 0.1.0
---
<!-- fleet-imperative: v3 -->
> **Invocation for `vc-{name}` (launcher `{name}`)** — table of three paths
> with **this** skill's literals. Link [DELEGATION_MATRIX.md](../DELEGATION_MATRIX.md).
> Foundation skills: state "no worker CLI" explicitly.
<!-- /fleet-imperative -->
# {Skill Title}
## Overview
{Brief description of what the skill does.}
## Dependencies
{List of required skills, if any.}
## Quick Start
{Minimal example using the real launcher literals.}
## Utility Scripts (if CLI-based)
{Document each subcommand with examples.}
## Workflow (if instruction-only)
{Numbered steps with clear instructions.}
## Rate Limiting (if applicable)
{Document rate limits and how they are enforced.}
## Common Mistakes
{List 2-3 common pitfalls — include "workflow paste" if relevant.}
## Verify before the handoff
{Link VERIFICATION_RULE.md when the skill can claim done.}
Rule 7: Progressive Disclosure
- Keep SKILL.md lean (~1.5–3k words). Move long procedures to
references/. - Do not copy the full Delegation Matrix into the skill body.
- Do not paste ERi /
vc-workflowrails onto non-workflow skills. - Prefer
tools/vc-skill-new.shfor greenfield scaffolding; this skill distills completed interactions.
Phase 4: Validation
After implementation is complete:
- Matrix check — invocation rail matches class; no generic
vibecrafted <workflow>blur; literals match skill name. - Skill-development check — third-person triggers, imperative body, progressive disclosure, examples present.
- Test the skill manually by invoking the agent with a natural-language prompt that should trigger the new skill.
- If a sample query/answer was provided during brainstorming, run it through the skill and verify the output matches expectations.
make test-skillswhen packaging into the vibecrafted skills tree.