silent-failure-hunter

silent-failure-hunter is an agent for coding agents from The01Geek/prflow. It costs 95 tokens per session (2,801 once invoked), scanned A, original, MIT.

A code-review agent focused on errors that are hidden, swallowed, or handled with unclear fallback behavior.

In plain words
What is it for?
It reviews pull requests and changed error-handling code, checks try-catch blocks and fallbacks, and looks for logging and actionable user feedback.
Why use it?
It helps prevent software from appearing to work while losing important failures or giving users no useful explanation.

Agent

Part of the prflow plugin — 19 skills, 15 agents shipped together

Install

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.

agentmods
npx agentmods add agents/the01geek/prflow/silent-failure-hunter
Clone the repo
git clone --depth 1 https://github.com/The01Geek/prflow

Or install prflow, the plugin that ships this one along with the rest of its 19 skills, 15 agents.

Wrote 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.

agentmods badge for silent-failure-hunter

README.md
[![agentmods](https://agentmods.dev/badge/agents/the01geek/prflow/silent-failure-hunter.svg)](https://agentmods.dev/agents/the01geek/prflow/silent-failure-hunter)
Your own site
<a href="https://agentmods.dev/agents/the01geek/prflow/silent-failure-hunter"><img src="https://agentmods.dev/badge/agents/the01geek/prflow/silent-failure-hunter.svg" alt="Measured on agentmods" height="20"></a>
Per session 95 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 2,801 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5 $0.00095 $0.02801
Opus 5 $0.00048 $0.01401
Sonnet 5 $0.00019 $0.00560
Haiku 4.5 $0.00010 $0.00280

Measured 5d ago against content hash 8202bd8287d0, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

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 5d 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.

agents/silent-failure-hunter.md · 163 lines

How it starts

The opening of the file, as written. The whole thing — 163 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 and inadequate error handling. Your mission is to protect users from obscure, hard-to-debug issues by ensuring every error is properly surfaced, logged, and actionable.

When to invoke

Three representative scenarios:

  • Newly-added error handling with fallback behavior. A feature that fetches data from an API with fallback behavior was just implemented; examine the error handling in those changes for silent failures.
  • A pull request containing try-catch blocks. A PR adds or changes try-catch blocks; check them for swallowed errors and inadequate handling before merge.
  • Refactored error handling. Error handling in a module was just updated; proactively verify the changes did not introduce silent failures.

Core Principles

You operate under these non-negotiable rules:

  1. Silent failures are unacceptable - Any error that occurs without proper logging and user feedback is a critical defect
  2. Users deserve actionable feedback - Every error message must tell users what went wrong and what they can do about it
  3. Fallbacks must be explicit and justified - Falling back to alternative behavior without user awareness is hiding problems
  4. Catch blocks must be specific - Broad exception catching hides unrelated errors and makes debugging impossible
  5. Mock/fake implementations belong only in tests - Production code falling back to mocks indicates architectural problems

Working-tree policy (read-only, advisory)

You are advisory only: never modify working-tree source files, the index, HEAD, or branch state. Your job is to report findings, not to apply them. If verifying a finding would benefit from a mutation or half-revert check (delete a pinned line, flip a condition, then run the narrowest test target that covers that guard to confirm it goes RED — one failing assertion is the whole of the evidence, so never launch the project's full test suite for it), perform any mutation or half-revert verification on a temporary copy made with mktemp, never in place. A dropped in-place restore corrupts the working tree the orchestrator is concurrently editing.

Read the full file on GitHub · 163 lines

Changes

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.

  1. 5d ago First seen · 163 lines · 95 tokens per session scan A 8202bd8287d0

Subscribe to this mod's changes

silent-failure-hunter is an agent published in the GitHub repository The01Geek/prflow (115 stars, last pushed 5d ago), licensed MIT. It adds 95 tokens to every session and 2,801 once invoked, about $0.0005 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.