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 skills/howells/arc/ideatenpx skills add howells/arc --skill ideategit clone --depth 1 https://github.com/howells/arcWhat 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 | $0.00051 | $0.04109 |
| Opus 5 | $0.00026 | $0.02055 |
| Sonnet 5 | $0.00010 | $0.00822 |
| Haiku 4.5 | $0.00005 | $0.00411 |
Grade A, and why
ideate 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 yesterday.
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 — 432 lines — stays where its author put it; the contents beside it link to each section on GitHub.
<hard_gate>
STOP — Structural Constraint
This skill has a LOCKED MESSAGE FORMAT during Act 1 (Understanding). You cannot override it.
Act 1 Message Format (MANDATORY)
Every message you send during Act 1 MUST follow this exact structure:
[0-2 sentences of context or acknowledgment]
[one question to the user — exactly ONE]
That's it. Nothing else. The message ends after the question.
Banned Output During Act 1
The following are STRUCTURALLY BANNED until the user has answered at least 3 questions AND you have explicitly transitioned to Act 2:
- Tables (markdown
|tables of any kind) - Data models or schemas
- Code blocks or pseudocode
- Bullet lists longer than 3 items
- Comparison charts
- Architecture descriptions
- Proposed approaches or recommendations
- "Here's what I understand so far" summaries longer than 2 sentences
- Any paragraph longer than 3 sentences
Violation Detection
Before sending ANY message during Act 1, run this checklist:
- Does the message contain a markdown table? → VIOLATION. Delete it.
- Does the message contain a code block? → VIOLATION. Delete it.
- Does the message contain more than 2 sentences before the AskUserQuestion? → VIOLATION. Cut it down.
- On a platform that has AskUserQuestion: does the message contain a "?" outside of AskUserQuestion? → VIOLATION. Move it into the tool. (On platforms without a structured question tool, such as Codex, the single plain-text question is expected — this check does not apply there.)
- Does the message propose any solution, approach, or design? → VIOLATION. Replace with a question about the user's intent.
- Is the message longer than 4 lines of text (excluding the tool call)? → VIOLATION. Shorten it.
If ANY check fails, rewrite the message before sending. Do not rationalize ("I'm just sharing context" or "This helps frame the question"). The format is the format.
Why This Exists
Four previous versions of this skill said "ask questions first" as advice. The model ignored it every time — producing comparison tables, data models, and full design proposals before asking a single question. Advisory language does not work. This structural constraint does. </hard_gate>
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.
- yesterday First seen · 432 lines · 51 tokens per session scan A 1a8921864615
ideate is a skill published in the GitHub repository howells/arc (25 stars, last pushed 17d ago), licensed MIT. It adds 51 tokens to every session and 4,109 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.
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