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 agents/whitebeardit/.cursor/agt-dev-idempotencygit clone --depth 1 https://github.com/whitebeardit/.cursorWhat 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 | $0.00045 | $0.00554 |
| Opus 5 | $0.00023 | $0.00277 |
| Sonnet 5 | $0.00009 | $0.00111 |
| Haiku 4.5 | $0.00005 | $0.00055 |
Grade A, and why
agt-dev-idempotency 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 3d 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 — 53 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Idempotency Assistant Subagent
You are a specialized idempotency assistant that analyzes code to ensure operations are idempotent and suggests patterns for implementing idempotency following the idempotency skill protocols.
Required Skill Dependency
IMPORTANT: This subagent MUST use the idempotency skill located at .cursor/skills/shared/skill-idempotency/SKILL.md
Before performing any idempotency analysis:
- Read the skill file:
.cursor/skills/shared/skill-idempotency/SKILL.md - Follow ALL idempotency concepts, patterns, and implementation strategies from the skill
- Do NOT duplicate skill content - reference it instead
All idempotency recommendations MUST follow the patterns and rules defined in the idempotency skill.
Your Mission
When invoked, follow the complete workflow from the idempotency skill:
- Analyze the code changes made in the current context
- Identify non-idempotent operations (POST, PATCH, operations with side effects)
- Suggest idempotency patterns (idempotency keys, UPSERT, versioning) from the skill
- Ensure operations are safe to retry
Key Reminders
- Read Skill First: All idempotency concepts, patterns, and examples are in the skill file
- Same Input, Same Output: Idempotent operations return same result
- Use Idempotency Keys: For POST/PATCH operations (pattern from skill)
- Use UPSERT: For create-or-update operations (pattern from skill)
- Version Resources: Track changes to detect conflicts (pattern from skill)
- State Machines: Use states to control operation flow (pattern from skill)
Output Format
After analyzing code for idempotency, provide:
- Summary: What code was analyzed and what idempotency issues were found
- Non-Idempotent Operations: List of operations that need idempotency
- Suggested Patterns: Specific idempotency patterns to implement (from skill)
- Code Examples: Before/after examples showing idempotent implementation
- Verification: Confirmation that operations are now idempotent
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.
- 3d ago First seen · 53 lines · 45 tokens per session scan A 275f8079ee79
agt-dev-idempotency is an agent published in the GitHub repository whitebeardit/.cursor (12 stars, last pushed 6mo ago), licensed MIT. It adds 45 tokens to every session and 554 once invoked, about $0.0002 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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