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 rules/jahands/prompts/error-messagesgit clone --depth 1 https://github.com/jahands/promptsWhat 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 | $0.00009 | $0.00284 |
| Opus 5 | $0.00005 | $0.00142 |
| Sonnet 5 | $0.00002 | $0.00057 |
| Haiku 4.5 | $0.00001 | $0.00028 |
Grade B, and why
error-messages scanned grade B with 1 finding 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.
Asks for rootmediumPrivilege escalation
A mod that escalates privileges can change anything on the machine, not only the project.
1. Check if PostgreSQL is running: `sudo systemctl status postgresql` What it actually says
What went wrong: The PostgreSQL connection timed out after 30 seconds.
Suggested fixes:
- Check if PostgreSQL is running:
sudo systemctl status postgresql - Verify your connection settings in
.env:- DATABASE_HOST should be 'localhost' or your server IP
- DATABASE_PORT should be 5432 (default)
- Test the connection manually:
psql -h localhost -U your_username -d your_database
</example>
</examples>
</error-messages-with-context>
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 · 36 lines · 9 tokens per session scan B dee3cb24f329
error-messages is a cursor rule published in the GitHub repository jahands/prompts (19 stars, last pushed 7mo ago), licensed MIT. It adds 9 tokens to every session and 284 once invoked, about $0.0000 per session on Opus 5. A static security scan graded it B with 1 finding (asks for root). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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