By haabe
Execute theory-grounded, evidence-gated product development from discovery to market using AI skills for simulated user interviews, opportunity solution trees, Wardley maps, bias mitigation, security audits, accessibility checks, threat modeling, metrics monitoring, and delivery validations with automated state management in .claude/ canvases.
npx claudepluginhub haabe/mycelium --plugin myceliumSystematically challenge current assumptions before major decisions. Counters confirmation bias, groupthink, and overconfidence.
Use to evaluate the current state of a diamond. Checks theory gates, confidence levels, and recommends next action.
Progress a diamond from one phase to the next. Runs all required theory gate checks, validates evidence, and at Deliver->Complete runs the executable Definition of Done checklist.
Assess delivery health metrics. For software: DORA + APEX. For content/AI/service products: product-type-appropriate metrics.
Run eval scenarios to benchmark Mycelium effectiveness. Execute tasks using reflexion loop, validate against success criteria, record metrics.
Parallel agent orchestration for OST exploration. Fan-out multiple solution explorations, fan-in results to compare and select winners.
Aggregate feedback signals across all active loops. Reports health, trajectory, overdue checks, regression warnings, and Goodhart's Law violations.
Evaluate Mycelium's own process effectiveness. Measures cycle velocity, discard trends, confidence calibration, gate effectiveness, regression rate. Run quarterly or every 20 cycles.
GIST planning workflow. Structure goals into ideas, steps, and tasks using Gilad's evidence-guided framework.
Generate structured handoff materials for offline human tasks (interviews, observations, outreach). Creates actionable briefs with phone-friendly capture templates.
Use to prioritize solutions or opportunities using ICE scoring with evidence-backed confidence.
Use when onboarding a new product/project. Progressive interview to understand purpose, vision, north star, and competitive landscape.
Map user Jobs to be Done across functional, emotional, and social dimensions. Based on Christensen's JTBD theory.
Classify releases into launch tiers and plan go-to-market. Based on Lauchengco's Loved framework.
Record findings from completed offline human tasks (interviews, observations, outreach) back into the canvas. The re-entry point after /mycelium:handoff.
Detect which external metric sources apply to this product (GitHub, Plausible, Stripe, etc.) and configure adapters. Retrofit entry point for projects that started before v0.14; also runnable to refresh source list when the product grows.
Pull snapshots from all configured metric sources, compute deltas against prior snapshots, flag unexplained signals, and draft evidence entries for canvas files. One entry point for all external product/market metrics.
Migrate a Mycelium project from legacy install (npx-degit, framework files in .claude/) to plugin install (framework lives in plugin cache, .claude/ holds project state only). Detects current install form, walks the user through plugin installation, runs the migration script, and verifies project state survived. Idempotent — safe to invoke on already-migrated projects.
Use when real user interviews aren't possible (solo/hobby/dogfood projects) but persona work is still needed. Enforces epistemic discipline: adversarial spectrum, pre-committed stop conditions, speculation tagging. NOT a substitute for /mycelium:user-interview when real users are available.
Use to build or update an Opportunity Solution Tree from research data. Never from brainstorming.
Smoke-test skill that confirms the Mycelium plugin loaded correctly. Returns a deterministic marker string for plugin-shape validation. Not for end-user invocation in normal use.
Use before starting delivery work. Pre-implementation validation checklist to ensure readiness.
Use to assess Privacy by Design compliance and GDPR/data protection alignment for a feature or system.
Accessibility audit against WCAG 2.1 AA. Checks semantic HTML, ARIA, keyboard navigation, color contrast, screen reader compatibility.
Design the smallest viable test to validate or invalidate a critical assumption. Based on Torres's assumption testing framework, organized by Gilad's AFTER model (Assessment → Fact-Finding → Tests → Experiments → Release Results).
Use before any research activity or significant decision. Reviews cognitive biases relevant to the current stage.
Use to evaluate whether current work aligns with Better Value Sooner Safer Happier. Run at diamond completion and periodically.
Lint canvas files for staleness, missing fields, inconsistent evidence types, and orphaned references. Run periodically or before major transitions.
Synchronize canvas state across team sessions via git. Ensures all team members see the same product knowledge.
Update canvas sections with new evidence. Ensures canvas stays current as the single source of truth.
Use to analyze correction trends, surface recurring patterns, and graduate repeat corrections to guardrails or anti-patterns.
Use when facing a new problem to classify its domain (Clear, Complicated, Complex, Chaotic, Confused) and select appropriate methods.
Use to verify a feature/story meets all Definition of Done criteria before marking complete.
Use when starting implementation on a new or unfamiliar codebase. Auto-detects tech stack and sets up development context.
A/B test CLAUDE.md instruction changes against eval benchmarks. Capture baselines, test variants, compare results.
Use for self-correcting implementation. Implements the reflexion loop: implement, validate, self-critique, retry (max 3 iterations).
Use to assess regulatory applicability for products that may fall under AI regulation (EU AI Act, Article 50 transparency).
Structured retrospective after completing a delivery increment or diamond. Captures learning for continuous improvement.
OWASP secure design review for code and architecture. Checks input validation, authentication, authorization, data protection.
Use to evaluate a service or feature against Downe's 15 principles of good services.
First-run setup for the Mycelium plugin. Creates project-state directories (.claude/canvas, .claude/diamonds, .claude/memory, .claude/harness) and minimal starter files in the user's project. Idempotent — re-running on an initialized project is a no-op. Run this once after installing the Mycelium plugin and before invoking other skills.
One command from "plugin installed" to "running brief on your idea." Combines /mycelium:setup (project-state initialization) and /mycelium:interview (10-minute discovery brief) into a single flow. Run this immediately after installing the Mycelium plugin — it's the recommended entry point for first-time users.
Assess team structure against Skelton's Team Topologies. Evaluate cognitive load, interaction modes, and Conway's Law alignment.
Use to conduct STRIDE threat modeling for a system or feature design.
Evaluate user-facing interfaces against Nielsen's 10 Usability Heuristics. Complements /mycelium:service-check (Downe = service-level quality, Nielsen = interface-level quality).
Guide for conducting Torres-style story-based user interviews with bias mitigation and JTBD lens.
Map user needs independently of solutions using Allen's User Needs Mapping methodology. Identifies underserved needs that feed into the Opportunity Solution Tree.
Create or update a Wardley Map of the value chain. Maps user needs, components, evolution stages, and strategic gameplay.
Explainability (XAI) audit for products containing AI components. Five-stage tier-scaled check: risk classification, stakeholder×question matrix, fidelity audit, system card, recourse path. Honest about what was validated functionally vs what needs user testing.
Executes bash commands
Hook triggers when Bash tool is used
Modifies files
Hook triggers on file write and edit operations
Share bugs, ideas, or general feedback.
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Sign in to claimAgent-first PM toolkit with 9 specialist agents and 18 skills for solo developers and small teams
Product discovery skills for PMs: ideation, experiments, assumption testing, feature prioritization, and customer interview synthesis.
Strategic thinking partner for product decisions. Works through problems conversationally, challenges assumptions, helps you ship faster. Grounded in frameworks from Marty Cagan, Teresa Torres, Elena Verna, Brian Balfour, Chip Huyen, Ryan Singer, Hamel Husain, and more. Complete eval chain from first 20 test cases through error analysis, LLM judges, and RAG evaluation. Plus backlog automation with Linear/GitHub integration.
Opportunity Solution Tree framework for pre-PMF startups to guide product discovery, problem validation, and solution prioritization
📋 Product Manager — Investigative Product Strategist + Market-Savvy PM
MUST use when user wants to plan or strategize a product/feature. 22 PM frameworks, 6 modes, multi-language, from idea to dev handoff
Your AI agent should think before it codes.
AI has made building cheap. It hasn't made deciding cheap. Agents will jump from an idea to a pull request without asking why, who for, or whether anyone needs it. Other tools accelerate delivery — Mycelium makes the agent earn the right to start.
# Recommended (post-v0.20.0): install as a Claude Code plugin
/plugin marketplace add haabe/mycelium
/plugin install mycelium@haabe-mycelium
/mycelium:start # one command: setup + 10-minute discovery
Plugin install is brownfield-safe: no project-root files are modified. Skills are namespaced as /mycelium:<name>. See docs/get-started.md for details.
On the namespace prefix. Anthropic's plugin convention requires /<plugin>:<skill>, so every Mycelium skill is /mycelium:foo. Two ergonomics that take the typing tax down:
/myc<Tab> in Claude Code and it expands to /mycelium:. Then a few letters of the skill name + <Tab> finishes it. /mycelium:diamond-assess is six keystrokes./... form is faster once you know the name; prose is fine when you don't.Legacy install (pre-v0.20.0, still supported during transition):
npx degit haabe/mycelium my-project && cd my-project
# Start Claude Code, then:
/interview
Build to learn, then build to earn (Patton). 30+ established frameworks, connected by theory gates so critical steps cannot be skipped. The agent does not progress until the evidence says it should. Discovery to market feedback at six scales (Purpose → Strategy → Opportunity → Solution → Delivery → Market), the same four-phase diamond at every scale. Configuration files plus orchestrated prompts — not a software library.
Builders — solo developers or small teams using AI agents to build products. If you can't afford to burn runway on the wrong thing, Mycelium helps you find the right thing before you build it.
Works for software, online courses, AI tools, and services. One command to start. The agent guides you from there.
Mycelium is for work where deciding what to build is the hard part. Some use cases are better served elsewhere — saying so up front saves frustration:
Time-constrained projects ARE supported as of 2026-04-30: /interview Phase 0 picks <8h inline discovery, 8-48h sprint mode, or 48h+ full interview. The path is selected by your answer to "How much time do you have?"
Not 45 skills dumped on you at once. Three modes that show up at the right time:
| When | Experience | Example |
|---|---|---|
| During a phase | Mentor | "Have you considered who your real user is? Here's what the research says about purpose statements." |
| At boundaries | Guardrail | "You're about to skip the bias check. The evidence gate requires this before progressing." |
| At transitions | Checklist | "Before moving forward: evidence ✓, bias check ✗, corrections ✓" |
A small project sees fewer gates and lighter guidance. A complex product gets the full treatment.
Mycelium has been dogfooded on three small projects AND tested by one outside user under realistic time pressure. Each session taught the framework something different — and most of what they taught is in the version you're looking at right now.