investigator-basic

investigator-basic is an agent for Claude Code from navapbc/digital-service-orchestra. It costs 31 tokens per session (2,226 once invoked), scanned A, a copy of investigator-advanced-code-tracer, Apache-2.0.

A basic bug investigation agent for locating the cause of simpler software problems in one pass.

In plain words
What is it for?
Use it to trace a straightforward bug back to its cause. It reports the finding and proposed fix for another agent or developer to implement.
Why use it?
It gives a quick, focused investigation for low-complexity bugs instead of requiring a lengthy analysis. It uses the five-whys method and suggests one fix.

Agent for Claude Code

Written for Claude Code: ${CLAUDE_PLUGIN_ROOT} variable. Also seen: model in frontmatter; mentions subagents; mentions Claude Code.

Runs only inside its plugin — its command needs a path that Claude Code sets for a plugin’s own hooks and for nothing else. Install the plugin, not this.

Part of the dso plugin — 37 skills, 4 commands, 53 agents shipped together

Good fit Use it to trace a straightforward bug back to its cause. It reports the finding and proposed fix for another agent or developer to implement.

Compare 6 agents from other repositories ↓
Install

Getting it into your agent

This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.

Claude Code
/plugin marketplace add navapbc/digital-service-orchestra
Claude Code
/plugin install dso

Made for: Claude Code.

Or install dso, the plugin that ships this one along with the rest of its 37 skills, 4 commands, 53 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 investigator-basic

README.md
[![agentmods](https://agentmods.dev/badge/agents/navapbc/digital-service-orchestra/investigator-basic/github.svg)](https://agentmods.dev/agents/navapbc/digital-service-orchestra/investigator-basic)
Your own site
<a href="https://agentmods.dev/agents/navapbc/digital-service-orchestra/investigator-basic"><img src="https://agentmods.dev/badge/agents/navapbc/digital-service-orchestra/investigator-basic/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.

agentmods 80×15 button for investigator-basic

Your own site · 80×15
<a href="https://agentmods.dev/agents/navapbc/digital-service-orchestra/investigator-basic"><img src="https://agentmods.dev/badge/agents/navapbc/digital-service-orchestra/investigator-basic.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 31 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 2,226 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 88% copy Near-identical to another mod 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 5.1 $0.00031 $0.02226
Opus 5 $0.00015 $0.01113
Sonnet 5 $0.00006 $0.00445
Haiku 4.5 $0.00003 $0.00223

Measured 9d ago against content hash a771ea2c1724, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

investigator-basic 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 9d 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.

Origin

This is a copy

88% identical to investigator-advanced-code-tracer — 65 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

plugins/dso/agents/investigator-basic.md · 191 lines

How it starts

The opening of the file, as written. The whole thing — 191 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Bug Investigator — Universal Base Guidance

This fragment is composed with a variant-specific delta file by build-composed-agents.sh --namespace investigator to produce a complete bug-investigator agent definition. It contains universal guidance that applies to all investigation tiers: role framing, context schema, empirical validation, self-reflection, RESULT schema, and rules.

Role

You are a bug investigator. Your task is to localize a bug to its root cause based on the context provided and report findings using the exact RESULT schema below. You perform investigation only — you do not implement fixes, modify source files, or dispatch sub-agents. The orchestrator that dispatched you will receive your RESULT and decide what to do.

The variant-specific guidance in your delta section describes your investigation lens (depth, technique, and any extra fields you must include in RESULT). Apply both this base and the delta in order — base first, delta last.

Startup: Session HEAD Sync (worktree isolation fix)

When the orchestrator dispatched you with isolation: "worktree", the Agent runtime created your worktree branched from origin/main — NOT from the orchestrator's session HEAD. If the orchestrator is on a session branch ahead of main with in-flight work (predecessor RED tests, freshly extracted libraries, new modules), your worktree starts WITHOUT that work and any investigation against absolute paths may read stale code. Bug a951-d6f2-0c21-443f tracks this.

Read the full file on GitHub · 191 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. 9d ago First seen · 191 lines · 31 tokens per session scan A a771ea2c1724

Subscribe to this mod's changes

investigator-basic is an agent published in the GitHub repository navapbc/digital-service-orchestra (6 stars, last pushed yesterday), licensed Apache-2.0. It adds 31 tokens to every session and 2,226 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 88% identical to investigator-advanced-code-tracer, differing in 65 lines, and is treated as a copy.