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.
npx agentmods add commands/ddunnock/claude-plugins/concept.blackboxgit clone --depth 1 https://github.com/ddunnock/claude-pluginsWhat 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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00028 | $0.01333 |
| Opus 5 | $0.00014 | $0.00666 |
| Sonnet 5 | $0.00006 | $0.00267 |
| Haiku 4.5 | $0.00003 | $0.00133 |
Grade A, and why
concept:blackbox 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 2d 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.
How it starts
The opening of the file, as written. The whole thing — 204 lines — stays where its author put it; the contents beside it link to each section on GitHub.
/concept:blackbox
Phase 3 of concept development: black-box architecture.
Prerequisites
Run the prerequisite gate check:
python3 ${CLAUDE_PLUGIN_ROOT}/scripts/update_state.py --state .concept-dev/state.json check-gate blackbox
If this exits non-zero, stop and tell the user to complete the previous phase first.
Then load context:
python3 ${CLAUDE_PLUGIN_ROOT}/scripts/update_state.py --state .concept-dev/state.json show- Read:
.concept-dev/PROBLEM-STATEMENT.md
Procedure
Step 1: Set Phase
python3 ${CLAUDE_PLUGIN_ROOT}/scripts/update_state.py --state .concept-dev/state.json set-phase blackbox
Step 2: Context Loading
Read .concept-dev/PROBLEM-STATEMENT.md and present:
===================================================================
BLACK-BOX ARCHITECTURE
===================================================================
Problem: [1-2 sentence summary]
Scope: [IN scope summary]
Key Constraints: [List]
I'll propose 2-3 high-level approaches to solving this problem.
Each approach describes WHAT the concept does at a functional level
— not HOW it's implemented.
For each approach, I'll describe:
- Functional blocks and their responsibilities
- Relationships between blocks
- Guiding principles
- Capabilities this architecture enables
- Trade-offs
===================================================================
Step 3: Propose Approaches
Use the concept-architect agent. Present 2-3 distinct architectural approaches:
===================================================================
APPROACH 1: [Name]
===================================================================
CONCEPT: [2-3 sentence description]
FUNCTIONAL BLOCKS:
[Block A] — [What it does, not how]
[Block B] — [What it does, not how]
[Block C] — [What it does, not how]
RELATIONSHIPS:
[Block A] → [Block B]: [What flows between them]
[Block B] ↔ [Block C]: [Bidirectional relationship]
PRINCIPLES:
1. [Guiding principle]
2. [Guiding principle]
ENABLES:
- [Capability this approach uniquely enables]
- [Capability]
TRADE-OFFS:
+ [Advantage]
+ [Advantage]
- [Disadvantage]
- [Disadvantage]
===================================================================
APPROACH 2: [Name]
===================================================================
[Same structure]
===================================================================
APPROACH 3: [Name]
===================================================================
[Same structure]
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.
- 2d ago First seen · 204 lines · 28 tokens per session scan A 13af26ae7dbd
concept:blackbox is a command published in the GitHub repository ddunnock/claude-plugins (12 stars, last pushed 5mo ago), licensed MIT. It adds 28 tokens to every session and 1,333 once invoked, about $0.0001 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.
Other commands, from other repositories
checklist
Generate a custom checklist for the current feature based on user requirements.
clarify
Identify underspecified areas in the current feature spec by asking up to 5 highly targeted clarification questions and encoding answers back into the spec.
specify
Create or update the feature specification from a natural language feature description.
analyze
Perform a non-destructive cross-artifact consistency and quality analysis across spec.md, plan.md, and tasks.md after task generation.
constitution
Create or update the project constitution from interactive or provided principle inputs.
converge
Assess the current codebase against the feature's spec, plan, and tasks, then append any remaining unbuilt work as new tasks to tasks.md so implement can complete it.