error-attacker

A code-scanning agent that looks for unsafe exception handling, such as ignored errors or missing resource cleanup, across Java, Python, JavaScript, PHP, and Ruby code.

In plain words
What is it for?
Use it to check code for empty catch blocks, swallowed exceptions, failure paths that stay open, overly broad exception handling, and missing finally blocks.
Why use it?
It helps find errors that code may hide or handle in a way that lets a program continue unsafely.

Agent

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/morodomi/dev-crew/error-attacker
Clone the repo
git clone --depth 1 https://github.com/morodomi/dev-crew
Per session 28 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 980 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 $0.00028 $0.00980
Opus 5 $0.00014 $0.00490
Sonnet 5 $0.00006 $0.00196
Haiku 4.5 $0.00003 $0.00098

Measured yesterday against content hash 30070ea73d9a, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

error-attacker 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.

agents/error-attacker.md · 89 lines

How it starts

The opening of the file, as written. The whole thing — 89 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Detection Targets

Type Description Pattern
empty-catch 空のcatch/exceptブロック catch (e) {}
swallowed-exception 例外の握りつぶし except: pass
fail-open 失敗時にオープン return true on error
generic-exception 汎用例外キャッチ catch (Exception e)
missing-finally リソース解放漏れ no finally block

Framework Detection Patterns

Framework Vulnerable Pattern Safe Pattern
Java catch (Exception e) {} catch (SpecificException e) { log(e); throw; }
Python except: pass except ValueError as e: logger.error(e)
JavaScript catch (e) {} catch (e) { console.error(e); throw e; }
PHP catch (Exception $e) {} catch (SpecificException $e) { Log::error($e); }

Dangerous Patterns

patterns:
  # Empty Catch (CWE-390)
  - 'catch\s*\([^)]*\)\s*\{\s*\}'           # JS/TS/PHP/Java
  - 'except:\s*pass'                         # Python
  - 'except\s+\w+:\s*pass'                   # Python specific
  - 'rescue\s*=>\s*nil'                      # Ruby
  - 'rescue\s*;\s*end'                       # Ruby empty

  # Swallowed Exception (CWE-391)
  - 'catch\s*\([^)]*\)\s*\{\s*//.*\s*\}'    # Comment only in catch
  - 'catch\s*\([^)]*\)\s*\{\s*/\*.*\*/\s*\}' # Block comment only
  - 'except.*:\s*#.*\n\s*pass'               # Python with comment

  # Fail Open (CWE-636)
  - 'catch\s*\([^)]*\)\s*\{[^}]*return\s+true'
  - 'except.*:\s*return\s+True'
  - 'rescue.*return\s+true'
  - 'on\s+error\s+resume\s+next'             # VB

  # Generic Exception (CWE-396)
  - 'catch\s*\(\s*Exception\s+\$?\w+\s*\)'   # PHP/Java
  - 'catch\s*\(\s*Throwable\s+\w+\s*\)'      # Java
  - 'except\s+Exception\s*:'                 # Python
  - 'except\s+BaseException\s*:'             # Python
  - 'catch\s*\(\s*\w+\s*\)\s*\{'             # JS catch any

  # Missing Finally (CWE-404)
  - 'try\s*\{[^}]*\}\s*catch[^f]*$'          # Try-catch without finally

Output

Base: {metadata: {scan_id, scanned_at, agent}, vulnerabilities: [{id, type, vulnerability_class, cwe_id, severity, file, line, code, description, remediation}], summary: {total, critical, high, medium, low}} Extra: prefix=ERR, types=empty-catch|swallowed-exception|fail-open|generic-exception|missing-finally

Read the full file on GitHub · 89 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. yesterday First seen · 89 lines · 28 tokens per session scan A 30070ea73d9a

Subscribe to this mod's changes

error-attacker is an agent published in the GitHub repository morodomi/dev-crew (1 stars, last pushed 3d ago), licensed MIT. It adds 28 tokens to every session and 980 once invoked, about $0.0001 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 2026-08-31.