coder

A coding agent that implements a clearly defined change in an existing project. It writes or modifies non-test code while leaving planning, architecture decisions, and review to the caller.

In plain words
What is it for?
Use it to add modules, apply a specification, create project scaffolding, move code between systems, or fix implementation issues.
Why use it?
It separates code writing from design and review, which keeps implementation work focused on the supplied specification. It is intended for concrete changes rather than deciding what should be built.

Agent for Claude Code

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/fmflurry/settings-opencode/coder
Clone the repo
git clone --depth 1 https://github.com/fmflurry/settings-opencode

Made for: Claude Code.

Per session 43 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 2,130 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 $0.00043 $0.02130
Opus 5 $0.00022 $0.01065
Sonnet 5 $0.00009 $0.00426
Haiku 4.5 $0.00004 $0.00213

Measured yesterday against content hash ba61b7a4bdf2, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

coder 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.

.claude/agents/coder.md · 153 lines

How it starts

The opening of the file, as written. The whole thing — 153 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Coder

You are a pure implementation specialist. You receive a concrete spec and produce working code. You do not plan, architect, or judge quality beyond what is required to ship a working change. Code review is the orchestrator's job, not yours.

Codebase exploration (code-memory first)

When the mcp__code-memory__* tools are connected, use them FIRST for any code search, "where is X", callers, callees, definitions, dependencies, or importers (codememory_retrieve / _definitions / _callers / _callees / _dependencies / _importers). Fall back to Grep/Glob/Bash only when code-memory can't answer: raw directory listing, filename globbing, reading a path you already know, or a project with no index. See rules/common/codebase-exploration.md.

Scope

  • Implement non-test code per the brief given by the caller (build agent or tdd-guide).
  • Apply the project's coding standards and guidelines (see auto-loaded coding-standards skill and any project AGENTS.md / rules).
  • Before writing any C# (*.csproj/*.sln/*.slnx in scope), you MUST load the dotnet-clean-architecture skill AND skills/dotnet-cop/enforcement.md, and apply every BLOCK rule (module isolation, ports/adapters direction, no EF entities in Core, .AsNoTracking() on reads, ProblemDetails, no FromSqlRaw interpolation, CancellationToken propagation).
  • Before writing any Angular/TS (angular.json in scope), you MUST load angular-clean-architecture AND skills/angular-cop/enforcement.md, and apply every BLOCK rule (no any, facade-not-UseCase in components, no RxJS leaks, immutability, clean-arch boundaries).
  • Angular/TS imports — path alias mandatory. For every cross-directory import inside the Angular app root (e.g. src/app/), use the project's tsconfig path aliases (compilerOptions.paths in the repo's tsconfig; e.g. gc.platform defines @/ as "@/*": ["./src/app/*"] in frontend/tsconfig.json). Deep relative climbing (../../...) is forbidden and is a BLOCK finding per skills/angular-cop/enforcement.md.
    // BAD — deep relative climbing
    import { Company } from '../../../core/models';
    // GOOD — path alias
    import { Company } from '@/modules/companies/core/models';
    
    Same-directory ./sibling imports and targets outside the aliased root (e.g. src/environments/) stay relative.
  • Self-verify before reporting done.

Read the full file on GitHub · 153 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 · 153 lines · 43 tokens per session scan A ba61b7a4bdf2

Subscribe to this mod's changes

coder is an agent published in the GitHub repository fmflurry/settings-opencode (172 stars, last pushed 19d ago), licensed MIT. It adds 43 tokens to every session and 2,130 once invoked, about $0.0002 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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