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 commands/wbern/agent-instructions/katagit clone --depth 1 https://github.com/wbern/agent-instructionsWhat 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 | $0.00011 | $0.04321 |
| Opus 5 | $0.00005 | $0.02160 |
| Sonnet 5 | $0.00002 | $0.00864 |
| Haiku 4.5 | $0.00001 | $0.00432 |
Grade A, and why
kata 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 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.
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 — 462 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Kata: TDD Practice Challenge Generator
Generate a complete TDD practice setup:
CHALLENGE.md- Problem description- Test file with first test placeholder
- Implementation file with empty function
General Guidelines
Output Style
- Never explicitly mention TDD in code, comments, commits, PRs, or issues
- Write natural, descriptive code without meta-commentary about the development process
- The code should speak for itself - TDD is the process, not the product
Beads is available for task tracking. Use mcp__beads__* tools to manage issues (the user interacts via bd commands).
Plan File Restriction
NEVER create, read, or update plan.md files. Claude Code's internal planning files are disabled for this project. Use other methods to track implementation progress (e.g., comments, todo lists, or external tools).
User arguments:
Kata: $ARGUMENTS
End of user arguments
(This command is interactive - arguments are ignored)
Data Source
Exercises from cyber-dojo (60 exercises, stable 10+ years).
- List:
https://api.github.com/repos/cyber-dojo/exercises-start-points/contents/start-points - Fetch:
https://raw.githubusercontent.com/cyber-dojo/exercises-start-points/master/start-points/{NAME}/readme.txt
Kata Categories
<kata_categories> <by_difficulty> Fizz_Buzz, Leap_Years, Prime_Factors, Word_Wrap, Closest_To_Zero, Remove_Duplicates, Array_Shuffle, Friday_13th, Five_Weekends, Number_Names, Print_Diamond, LCD_Digits, Fisher_Yates_Shuffle Roman_Numerals, Reverse_Roman, Bowling_Game, Tennis, Anagrams, ISBN, Balanced_Parentheses, Calc_Stats, Recently_Used_List, Phone_Numbers, Combined_Number, Group_Neighbours, Longest_Common_Prefix, Yatzy, Yatzy_Cutdown, Harry_Potter, Vending_Machine, Count_Coins, 100_doors, Haiku_Review, ABC_Problem, Align_Columns, Best_Shuffle, Filename_Range, Unsplice, 12_Days_of_Xmas Game_of_Life, Mars_Rover, Mine_Sweeper, Mine_Field, Eight_Queens, Knights_Tour, Reversi, Poker_Hands, Levenshtein_Distance, Magic_Square, Saddle_Points, Tiny_Maze, Gray_Code, Monty_Hall, Number_Chains, Wonderland_Number, Zeckendorf_Number, Diff_Selector, Diversion, Reordering, Fizz_Buzz_Plus </by_difficulty>
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.
- 2d ago First seen · 462 lines · 11 tokens per session scan A fba292d49a65
kata is a command published in the GitHub repository wbern/agent-instructions (168 stars, last pushed 3mo ago), licensed MIT. It adds 11 tokens to every session and 4,321 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 2026-08-30.
Other commands, from other repositories
checklist
Generate a custom checklist for the current feature based on user requirements.
clarify
Identify underspecified areas in the current feature spec by asking up to 5 highly targeted clarification questions and encoding answers back into the spec.
specify
Create or update the feature specification from a natural language feature description.
analyze
Perform a non-destructive cross-artifact consistency and quality analysis across spec.md, plan.md, and tasks.md after task generation.
converge
Assess the current codebase against the feature's spec, plan, and tasks, then append any remaining unbuilt work as new tasks to tasks.md so implement can complete it.
implement
Execute the implementation plan by processing and executing all tasks defined in tasks.md.