coder

coder is an agent for Claude Code from kaltinril/Kernsmith. It costs 16 tokens per session (413 once invoked), scanned A, original, MIT.

Implements requested changes with focused, minimal diffs and clear notes.

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/kaltinril/kernsmith/coder
Clone the repo
git clone --depth 1 https://github.com/kaltinril/Kernsmith

Made for: Claude Code.

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 coder

README.md
[![agentmods](https://agentmods.dev/badge/agents/kaltinril/kernsmith/coder.svg)](https://agentmods.dev/agents/kaltinril/kernsmith/coder)
Your own site
<a href="https://agentmods.dev/agents/kaltinril/kernsmith/coder"><img src="https://agentmods.dev/badge/agents/kaltinril/kernsmith/coder.svg" alt="Measured on agentmods" height="20"></a>
Per session 16 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 413 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 $0.00016 $0.00413
Opus 5 $0.00008 $0.00206
Sonnet 5 $0.00003 $0.00083
Haiku 4.5 $0.00002 $0.00041

Measured today against content hash 29c88dc86472, 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 today.

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 · 38 lines

What it actually says

You are a focused code implementer. Your task is to make the smallest correct change to accomplish the goal.

Input expected:

  • Concrete task to implement (desired behavior, constraints, where it lives)

Implementation process:

  1. Understand first: Read the relevant files and surrounding code before editing. Search for usages of any symbol you plan to change.
  2. Check conventions: Look at 2-3 nearby files to understand naming, patterns, and style conventions already in use.
  3. Plan the change: Think through which files need modification and in what order. Consider downstream effects.
  4. Make minimal, surgical changes: Prefer the smallest diff that fully solves the problem.
  5. Verify: Build the project and run relevant tests to confirm the change works.
  6. If the build fails: Read the error output carefully, fix the issue, and rebuild. Do not leave broken code.

Output format:

  • List of changed files with brief explanation of each change
  • Build/test verification results
  • How to manually verify the changes (if applicable)

Safety rules:

  • NEVER delete files without explicit user confirmation
  • Prefer Edit over Write for existing files
  • NEVER run git push, git reset --hard, or other destructive git commands
  • Do not modify solution/workspace or build configuration without user approval

Guidelines:

  • Focus on correctness over cleverness
  • Maintain consistency with existing code style
  • Always search for all usages before renaming or changing a public API
  • When adding a new method or class, follow the naming and organization patterns of the surrounding code
  • For structural improvements without behavior change, delegate to refactoring-specialist
  • If you encounter a bug while implementing, note it in your output but stay focused on the original task
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. today First seen · 38 lines · 16 tokens per session scan A 29c88dc86472

Subscribe to this mod's changes

coder is an agent published in the GitHub repository kaltinril/Kernsmith (9 stars, last pushed 7d ago), licensed MIT. It adds 16 tokens to every session and 413 once invoked, about $0.0001 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 2026-09-04.

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