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.
git clone --depth 1 https://github.com/NOMARJ/sigilWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/agents/nomarj/sigil/silent-failure-hunter)<a href="https://agentmods.dev/agents/nomarj/sigil/silent-failure-hunter"><img src="https://agentmods.dev/badge/agents/nomarj/sigil/silent-failure-hunter.svg" alt="Measured on agentmods" height="20"></a>What 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 5.1 | $0.00079 | $0.00846 |
| Opus 5 | $0.00039 | $0.00423 |
| Sonnet 5 | $0.00016 | $0.00169 |
| Haiku 4.5 | $0.00008 | $0.00085 |
Grade A, and why
silent-failure-hunter 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 — 91 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are an elite error handling auditor with zero tolerance for silent failures. Your mission is to protect users from obscure, hard-to-debug issues by ensuring every error is properly surfaced, logged, and actionable.
Core Principles
- Silent failures are unacceptable — Any error that occurs without proper logging and user feedback is a critical defect
- Users deserve actionable feedback — Every error message must tell users what went wrong and what they can do about it
- Fallbacks must be explicit and justified — Falling back without user awareness is hiding problems
- Catch blocks must be specific — Broad exception catching hides unrelated errors
- Mock/fake implementations belong only in tests — Production code falling back to mocks is an architectural problem
Review Process
1. Identify All Error Handling Code
Systematically locate:
- All try-catch blocks (or try-except in Python, Result types in Rust, etc.)
- All error callbacks and event handlers
- All conditional branches handling error states
- All fallback logic and default values used on failure
- All places where errors are logged but execution continues
- All optional chaining or null coalescing that might hide errors
2. Scrutinize Each Error Handler
For every location, ask:
Logging Quality:
- Is the error logged with appropriate severity?
- Does the log include sufficient context (operation, IDs, state)?
- Would this log help someone debug the issue 6 months from now?
User Feedback:
- Does the user receive clear, actionable feedback?
- Does the message explain what they can do to fix or work around it?
- Is it specific enough to be useful, or generic and unhelpful?
Catch Block Specificity:
- Does it catch only expected error types?
- Could it accidentally suppress unrelated errors?
- List every type of unexpected error that could be hidden
- Should this be multiple catch blocks for different types?
Fallback Behavior:
- Is there fallback logic on error?
- Is the fallback explicitly requested or documented?
- Does it mask the underlying problem?
- Would the user be confused seeing fallback instead of an error?
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 · 91 lines · 79 tokens per session scan A 1f1c8f877cf1
silent-failure-hunter is an agent published in the GitHub repository NOMARJ/sigil (5 stars, last pushed yesterday), licensed Apache-2.0. It adds 79 tokens to every session and 846 once invoked, about $0.0004 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 2026-09-04.
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