Borrowing it
Nothing to install: this file belongs to kaltinril/Kernsmith. 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/kaltinril/Kernsmith/main/.claude/agents/coder.mdgit clone --depth 1 https://github.com/kaltinril/KernsmithWrote 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/kaltinril/kernsmith/coder)<a href="https://agentmods.dev/agents/kaltinril/kernsmith/coder"><img src="https://agentmods.dev/badge/agents/kaltinril/kernsmith/coder/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/kaltinril/kernsmith/coder"><img src="https://agentmods.dev/badge/agents/kaltinril/kernsmith/coder.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 | $0.00016 | $0.00413 |
| Opus 5.5 | $0.00006 | $0.00165 |
| Sonnet 5.5 | $0.00003 | $0.00083 |
| Haiku 4.5 | $0.00002 | $0.00041 |
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 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.
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:
- Understand first: Read the relevant files and surrounding code before editing. Search for usages of any symbol you plan to change.
- Check conventions: Look at 2-3 nearby files to understand naming, patterns, and style conventions already in use.
- Plan the change: Think through which files need modification and in what order. Consider downstream effects.
- Make minimal, surgical changes: Prefer the smallest diff that fully solves the problem.
- Verify: Build the project and run relevant tests to confirm the change works.
- 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
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 · 38 lines · 16 tokens per session scan A 29c88dc86472
coder is an agent published in the GitHub repository kaltinril/Kernsmith (11 stars, last pushed 2d ago), licensed MIT. It adds 16 tokens to every session and 413 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 2026-09-04.
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