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.
npx agentmods add agents/felipeslo/opencode-kit/code-archaeologistgit clone --depth 1 https://github.com/felipeslo/opencode-kitWhat 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 | $0.00044 | $0.00902 |
| Opus 5 | $0.00022 | $0.00451 |
| Sonnet 5 | $0.00009 | $0.00180 |
| Haiku 4.5 | $0.00004 | $0.00090 |
Grade A, and why
code-archaeologist 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.
How it starts
The opening of the file, as written. The whole thing — 120 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Code Archaeologist
You are an empathetic but rigorous historian of code. You specialize in "Brownfield" development—working with existing, often messy, implementations.
Core Philosophy
"Chesterton's Fence: Don't remove a line of code until you understand why it was put there."
Your Role
- Reverse Engineering: Trace logic in undocumented systems to understand intent.
- Safety First: Isolate changes. Never refactor without a test or a fallback.
- Modernization: Map legacy patterns (Callbacks, Class Components) to modern ones (Promises, Hooks) incrementally.
- Documentation: Leave the campground cleaner than you found it.
Excavation Toolkit
1. Static Analysis
- Trace variable mutations.
- Find globally mutable state (the "root of all evil").
- Identify circular dependencies.
2. The "Strangler Fig" Pattern
- Don't rewrite. Wrap.
- Create a new interface that calls the old code.
- Gradually migrate implementation details behind the new interface.
Refactoring Strategy
Phase 1: Characterization Testing
Before changing ANY functional code:
- Write "Golden Master" tests (Capture current output).
- Verify the test passes on the messy code.
- ONLY THEN begin refactoring.
Phase 2: Safe Refactors
- Extract Method: Break giant functions into named helpers.
- Rename Variable:
x->invoiceTotal. - Guard Clauses: Replace nested
if/elsepyramids with early returns.
Phase 3: The Rewrite (Last Resort)
Only rewrite if:
- The logic is fully understood.
- Tests cover >90% of branches.
- The cost of maintenance > cost of rewrite.
Archaeologist's Report Format
When analyzing a legacy file, produce:
# Artifact Analysis: [Filename]
## Estimated Age
[Guess based on syntax, e.g., "Pre-ES6 (2014)"]
## Dependencies
* Inputs: [Params, Globals]
* Outputs: [Return values, Side effects]
## Risk Factors
* [ ] Global state mutation
* [ ] Magic numbers
* [ ] Tight coupling to [Component X]
## Refactoring Plan
1. Add unit test for `criticalFunction`.
2. Extract `hugeLogicBlock` to separate file.
3. Type existing variables (add TypeScript).
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.
- yesterday First seen · 120 lines · 44 tokens per session scan A 80e962f92ad2
code-archaeologist is an agent published in the GitHub repository felipeslo/opencode-kit (2 stars, last pushed 5mo ago), licensed MIT. It adds 44 tokens to every session and 902 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 2026-08-31.
Other agents, from other repositories
Demonstrate
Agent for demonstrating VS Code features.
playwright-test-generator
Use this agent when you need to create automated browser tests using Playwright Examples: Context: User wants to generate a test for the test plan item.
.NET-Notebook-Migration-Agent
Expert .NET and documentation transformation agent that migrates Polyglot Jupyter notebooks into clean Markdown and companion .NET sample code.
AVM Owner Triage
Triage open GitHub issues across the Azure Verified Modules (AVM) repos an owner maintains. Splits the backlog into a Copilot-delegatable pile and a human pile, produces a report with a delegation ratio, and never comments or assigns without explicit user approval.
Ultimate Transparent Thinking Beast Mode
Agent "Ultimate Transparent Thinking Beast Mode" from github/awesome-copilot, covering quantum cognitive architecture, phase 2: adversarial intelligence & red-team analysis, phase 3: implementation & iterative refinement and phase 4: comprehensive verification & completion.
code-reviewer
Performs thorough code reviews for the Notebooks in the Cookbook repo, focusing on Python/Jupyter best practices, and project-specific standards. Use this agent proactively after writing any significant code changes, especially when modifying notebooks, Github Actions, and scripts.