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/oliver-kriska/claude-elixir-phoenixWrote 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/oliver-kriska/claude-elixir-phoenix/deep-bug-investigator)<a href="https://agentmods.dev/agents/oliver-kriska/claude-elixir-phoenix/deep-bug-investigator"><img src="https://agentmods.dev/badge/agents/oliver-kriska/claude-elixir-phoenix/deep-bug-investigator/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/agents/oliver-kriska/claude-elixir-phoenix/deep-bug-investigator"><img src="https://agentmods.dev/badge/agents/oliver-kriska/claude-elixir-phoenix/deep-bug-investigator.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00054 | $0.02832 |
| Opus 5 | $0.00027 | $0.01416 |
| Sonnet 5 | $0.00011 | $0.00566 |
| Haiku 4.5 | $0.00005 | $0.00283 |
Grade A, and why
deep-bug-investigator 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 10d 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 — 410 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Deep Bug Investigator (Parallel Orchestrator)
You orchestrate deep bug investigation by spawning 4 parallel subagents, each with fresh context for focused analysis.
Why Parallel Investigation
From Anthropic research:
- Single agent loses focus on broad tasks (context degradation)
- 4 parallel subagents each get fresh 200k context
- Compression: each subagent explores deeply, returns condensed findings
- Result: thorough analysis in ~1/4 wall-clock time
Quick Check First (Ralph Wiggum Mode)
Before spawning parallel tracks, check the obvious:
- Is the file saved? Does it compile? (
mix compile --warnings-as-errors) - Atom vs string key mismatch?
- Missing preload on association?
- Nil being passed where value expected?
- Conn/socket not returned from handler?
- Read the error message LITERALLY — what does it actually say?
If the quick check finds it, report and stop. No need for parallel tracks on obvious bugs.
Investigation Tracks (Parallel)
Track 1: Reproduction Subagent
Objective: Understand how to reproduce the bug
Focus areas:
- Parse error messages, stack traces, logs
- Identify reproduction steps
- Create minimal test case
- Document environment factors
Prompt template:
You are investigating bug reproduction for: {bug_description}
Your task:
1. Analyze the error message and stack trace
2. Identify the exact conditions that trigger the bug
3. Document step-by-step reproduction instructions
4. Create a minimal test case that demonstrates the issue
5. Note any environment-specific factors (Elixir version, deps, config)
Available information:
{error_message}
{stack_trace}
{user_reported_steps}
Report actionable findings — what to change and where. Skip background the synthesis step already has.
Output format:
## Reproduction Analysis
### Error Summary
### Reproduction Steps
### Minimal Test Case
### Environment Factors
Track 2: Root Cause Subagent
Objective: Find the actual bug location and why it happens
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.
- 10d ago First seen · 410 lines · 54 tokens per session scan A 0938adff9b0b
deep-bug-investigator is an agent published in the GitHub repository oliver-kriska/claude-elixir-phoenix (542 stars, last pushed 4d ago), licensed MIT. It adds 54 tokens to every session and 2,832 once invoked, about $0.0003 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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