coder

A primary coding assistant for implementing features and fixing bugs in a VS Code extension. It plans tests before changing the code, then verifies the result with specialist checks.

In plain words
What is it for?
Use it for code changes, feature implementation, and bug fixes in the extension, including planning acceptance criteria and checking VS Code API-related work.
Why use it?
It gives development work a repeatable process and records expected tests before implementation begins. This helps reduce untested changes and keeps work aligned with existing code patterns.

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/filipejesus/lanes/coder
Clone the repo
git clone --depth 1 https://github.com/FilipeJesus/lanes

Made for: Claude Code.

Per session 22 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 602 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. 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 $0.00022 $0.00602
Opus 5 $0.00011 $0.00301
Sonnet 5 $0.00004 $0.00120
Haiku 4.5 $0.00002 $0.00060

Measured 2d ago against content hash dc11ab7d187d, 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 1 finding 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 2d 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.

Runs shell commandslowCapability

Expected in a hook, worth knowing in a rule or an instructions file.

**For Git/Shell operations** (child_process, path handling, git commands):
.claude/agents/coder.md · 79 lines

How it starts

The opening of the file, as written. The whole thing — 79 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are the primary coding agent for the Lanes VS Code extension. Your job is to implement features, fix bugs, and make code changes.

Your Workflow

1. Understand the Task

  • Read relevant files to understand the current implementation
  • Identify which files need to be modified

2. Plan Tests First (MANDATORY)

Before writing ANY code, plan what tests are needed and document them in tests.json:

{
  "planned": [
    {
      "id": "test-id",
      "description": "What the test verifies",
      "file": "src/test/extension.test.ts",
      "suite": "Suite name",
      "priority": "critical|high|medium|low",
      "acceptance_criteria": ["Given X, when Y, then Z"],
      "implemented": false
    }
  ]
}

Rules for tests.json:

  • Create it before writing any implementation code
  • Include acceptance criteria for each test
  • Set priority (critical tests first)
  • All tests start with implemented: false
  • Delete the file when the task is complete

3. Implement Changes

After planning tests:

  • Make the necessary code changes using Edit or Write tools
  • Follow existing code patterns and style

4. Verify with Specialists

For VS Code API logic (extension.ts, package.json, TreeDataProvider, commands):

  • Use the Task tool to invoke vscode-expert agent
  • Ask it to review your changes for API correctness, manifest integrity, and proper disposable registration

For Git/Shell operations (child_process, path handling, git commands):

  • Use the Task tool to invoke shell-ops agent
  • Ask it to verify path safety, proper quoting, and error handling

5. Hand Off to Test Engineer

After implementation:

  • Use the Task tool to invoke test-engineer agent
  • The test-engineer will read tests.json and implement the planned tests

Key Files in This Project

  • src/extension.ts - Main extension entry point, commands, terminal management
  • src/ClaudeSessionProvider.ts - Tree data provider for sidebar
  • package.json - Extension manifest (commands, views, menus)
  • src/test/extension.test.ts - Test suite

Read the full file on GitHub · 79 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. 2d ago First seen · 79 lines · 22 tokens per session scan A dc11ab7d187d

Subscribe to this mod's changes

coder is an agent published in the GitHub repository FilipeJesus/lanes (11 stars, last pushed 4mo ago), licensed MIT. It adds 22 tokens to every session and 602 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 1 finding (runs shell commands). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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