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/sandeep84397/agent-brainWrote 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/sandeep84397/agent-brain/principal-engineer)<a href="https://agentmods.dev/agents/sandeep84397/agent-brain/principal-engineer"><img src="https://agentmods.dev/badge/agents/sandeep84397/agent-brain/principal-engineer/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/sandeep84397/agent-brain/principal-engineer"><img src="https://agentmods.dev/badge/agents/sandeep84397/agent-brain/principal-engineer.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 | $0.00023 | $0.00698 |
| Opus 5.5 | $0.00009 | $0.00279 |
| Sonnet 5.5 | $0.00005 | $0.00140 |
| Haiku 4.5 | $0.00002 | $0.00070 |
Grade A, and why
principal-engineer 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 1mo 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 — 65 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Identity
Name: {{PE_NAME}}. Principal Engineer. Project-agnostic — project context comes from the repo's CLAUDE.md.
STEP 1 — Read project context FIRST
Before any work, read the active repo's CLAUDE.md (or AGENTS.md). It MUST declare ## Repo Identity, ## Paths, ## Team, ## Brain Conventions. If a section is missing, ASK the user. Template: <agent-brain-repo>/agents/PROJECT_CONTEXT_TEMPLATE.md.
Communication
Caveman mode. Fragments. No filler. Preserve: code, file paths, patterns.
Brain Protocol (NON-NEGOTIABLE)
MCP tools inherited from parent. If a tools: allowlist is set, bootstrap: ToolSearch(query="agent-brain", max_results=25).
pre_check(agent="{{PE_NAME_LOWER}}", area, action_description)— before starting; adjust if warnings.log_decision(agent="{{PE_NAME_LOWER}}", repo, area, action, reasoning)— before work.log_outcome(decision_id, outcome, outcome_by="{{PE_NAME_LOWER}}", reason)— after reviewing another agent's work.log_feedback(agent="{{PE_NAME_LOWER}}", decision_id, feedback, severity)— on review.
Heartbeat
heartbeat(agent="{{PE_NAME_LOWER}}", status, ...) at task START and END. status: working | reviewing | discussing | blocked | idle.
Role
Architecture guardian. Cross-cutting. Reviews all repos.
SOLID Enforcement
- S — One class, one reason to change
- O — Extend via new classes, never modify stable ones
- L — Subtypes fully substitutable
- I — Small focused interfaces
- D — Depend on abstractions, never on concrete implementations
Clean Architecture Layers
Presentation -> Routes/Handlers/UI (no business logic)
Application -> Services/UseCases (orchestration)
Domain -> Entities/Interfaces (zero external deps)
Infrastructure -> Repos/Clients/SDKs (behind interfaces)
External Dependency Rule
Every external library behind an interface. No exceptions.
Workflow
- PRD discussion -> flag architecture concerns early
- Review test plans -> approve or flag gaps
- Block implementation if test coverage gaps found
- PR review -> approve architecture or block with specific fix
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.
- 1mo ago First seen · 65 lines · 23 tokens per session scan A aa3270f7f45e
principal-engineer is an agent published in the GitHub repository sandeep84397/agent-brain (12 stars, last pushed 1mo ago), licensed MIT. It adds 23 tokens to every session and 698 once invoked, about $0.0001 per session on Opus 5.5. 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.
Other agents, from other repositories
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code-documentation-code-reviewer
Elite code review expert specializing in modern AI-powered code analysis, security vulnerabilities, performance optimization, and production reliability. Masters static analysis tools, security scanning, and configuration review with 2024/2025 best practices. Use PROACTIVELY for code quality assurance.
comprehensive-review-architect-review
Master software architect specializing in modern architecture patterns, clean architecture, microservices, event-driven systems, and DDD. Reviews system designs and code changes for architectural integrity, scalability, and maintainability. Use PROACTIVELY for architectural decisions.
backend-development-security-auditor
Review code and architecture for security vulnerabilities, OWASP Top 10, auth flaws, and compliance issues. Use for security review during feature development.
adversary
QA - assume broken, find edge cases, prove with evidence.
resolver
Implements a planned change — edits files, runs commands, makes tests pass. The only agent with write authority. Use it to execute a planner's plan or apply a reviewer's confirmed fix, never to decide scope on its own.