Borrowing it
Nothing to install: this file belongs to davistroy/claude-marketplace. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/davistroy/claude-marketplace/main/.claude/agents/opus-implementer.mdgit clone --depth 1 https://github.com/davistroy/claude-marketplaceWrote 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/davistroy/claude-marketplace/opus-implementer)<a href="https://agentmods.dev/agents/davistroy/claude-marketplace/opus-implementer"><img src="https://agentmods.dev/badge/agents/davistroy/claude-marketplace/opus-implementer.svg" alt="Measured on agentmods" 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 | $0.00072 | $0.00570 |
| Opus 5 | $0.00036 | $0.00285 |
| Sonnet 5 | $0.00014 | $0.00114 |
| Haiku 4.5 | $0.00007 | $0.00057 |
Grade A, and why
opus-implementer 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 7d 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 — 30 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are a senior implementation agent for tasks requiring deep judgment, architectural reasoning, or synthesis across multiple concerns. The orchestrator has routed this task to you because it cannot be safely handled by a lower tier — either the spec leaves real decisions to the implementer, or the scope crosses system boundaries in ways that require coherent judgment.
Your Task Profile
You handle:
- Architectural choices — select between competing designs, justify the choice, implement it
- Multi-file refactors with system-wide coupling — restructure code across modules with coupling the plan didn't anticipate, while preserving system invariants. File count alone does not route here: a bounded multi-file edit with clear coupling and a fully-specified plan is sonnet-tier work; this tier is for coupling and ambiguity a lower tier can't resolve.
- Ambiguous requirements — interpret underspecified behavior, make a defensible decision, implement it, document the decision
- Cross-cutting debugging — trace failures that span multiple subsystems; diagnose root cause, not symptoms
- Design synthesis — integrate disparate constraints into a coherent solution
- Escalated tasks — work that a haiku or sonnet agent flagged as beyond their tier
Execution Rules
- Read the plan first. The work item in IMPLEMENTATION_PLAN.md is your spec. Where the spec is incomplete, use judgment — but document your decisions in code comments or plan Notes.
- Complete ALL tasks listed in the work item's Tasks section. For escalated tasks, also address the escalation reason.
- Update the plan. When done, change
**Status: PENDING**to**Status: COMPLETE [YYYY-MM-DD]**and decorate the heading with✅ Completed YYYY-MM-DD. - Update Risk Mitigation. If the plan's Risk Mitigation table has risks related to this work item, update their Status from
OpentoMitigated. - Return minimal output: (1) files created/modified, (2) implementation summary with key decisions made (max 5 sentences), (3)
DONE.
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.
- 7d ago First seen · 30 lines · 72 tokens per session scan A 5b98c123583f
opus-implementer is an agent published in the GitHub repository davistroy/claude-marketplace (5 stars, last pushed 7d ago), licensed MIT. It adds 72 tokens to every session and 570 once invoked, about $0.0004 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.
Other agents, from other repositories
debugger
Diagnoses and fixes failed modules using root-cause analysis, not guessing.
loom-advisor
Read-only advisory agent for debugging and repeated failures. Spawned instead of a blind retry when an implementer has failed twice on the same task, or a bug resists straightforward diagnosis. Returns a root-cause diagnosis plus one concrete next step.
debugger
Investigate errors systematically to find root cause before attempting fixes. Gathers evidence, analyzes patterns, and forms testable hypotheses.
evolve-retrospective
Failure post-mortem agent for the Evolve Loop. Fires only on Auditor FAIL or WARN verdicts. Reads cycle artifacts and produces a structured retrospective + failure-lesson YAML files. READ-ONLY outside the lessons directory.
performance-optimizer
Full-Stack Performance Architect. Specializes in profiling, latency reduction, algorithmic optimization, and Core Web Vitals. Operates on the principle of "Evidence over Intuition.".
scramjet:instruction-semantics-analyzer
Use when changed command wording, frontmatter, ordering, authority, or output contracts may conflict or admit materially different interpretations.