Borrowing it
Nothing to install: this file belongs to davidmatousek/tachi. 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/davidmatousek/tachi/main/.claude/skills/tachi-shared/SKILL.mdgit clone --depth 1 https://github.com/davidmatousek/tachiWrote 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/skills/davidmatousek/tachi/tachi-shared)<a href="https://agentmods.dev/skills/davidmatousek/tachi/tachi-shared"><img src="https://agentmods.dev/badge/skills/davidmatousek/tachi/tachi-shared/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/skills/davidmatousek/tachi/tachi-shared"><img src="https://agentmods.dev/badge/skills/davidmatousek/tachi/tachi-shared.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00056 | $0.00724 |
| Opus 5.5 | $0.00022 | $0.00290 |
| Sonnet 5.5 | $0.00011 | $0.00145 |
| Haiku 4.5 | $0.00006 | $0.00072 |
Grade A, and why
tachi-shared 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.
How it starts
The opening of the file, as written. The whole thing — 40 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Tachi Shared References
Cross-cutting domain knowledge consumed by multiple tachi agents. These reference files are the canonical source of truth for definitions that appear across the pipeline -- severity bands, STRIDE+AI threat categories, and finding format conventions. Individual agents load specific references on-demand using the Read tool rather than duplicating definitions inline.
Domain Coverage
This skill contains four shared reference files:
-
Severity Bands -- Composite score thresholds, severity band boundaries, color codes, SLA mappings, disposition defaults, and review date calculations. Used everywhere severity classification drives decisions.
-
STRIDE+AI Categories -- All 11 threat categories (6 STRIDE + 5 AI) with descriptions, ID prefixes, OWASP references, and the DFD element-to-category applicability matrix that determines which categories apply to which component types.
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Finding Format -- The finding intermediate representation (IR) specification: required fields, optional fields, ID format conventions, validation rules, and table output format. Defines the contract between threat agents (producers) and downstream consumers.
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MAESTRO Layers -- CSA MAESTRO seven-layer taxonomy definitions for agentic AI architectures: layer identifiers (L1-L7), descriptions, keyword-to-layer mappings, and the classification algorithm (first-match-wins, "Unclassified" default). Used during Phase 1 to classify components by architectural layer.
Loading Table
| Reference File | Consumers | Load When |
|---|---|---|
references/severity-bands-shared.md |
orchestrator, risk-scorer, control-analyzer, threat-report, threat-infographic, report-assembler | When severity classification, SLA computation, governance field derivation, or severity-based formatting is needed |
references/stride-categories-shared.md |
orchestrator, spoofing, tampering, repudiation, info-disclosure, denial-of-service, privilege-escalation, prompt-injection, data-poisoning, model-theft, agent-autonomy, tool-abuse | When category definitions, DFD applicability rules, or category-to-agent mapping is needed |
references/finding-format-shared.md |
orchestrator, spoofing, tampering, repudiation, info-disclosure, denial-of-service, privilege-escalation, prompt-injection, data-poisoning, model-theft, agent-autonomy, tool-abuse, risk-scorer | When producing or consuming finding records, validating finding structure, or assembling output tables |
references/maestro-layers-shared.md |
orchestrator, risk-scorer, control-analyzer, threat-report | When classifying components by MAESTRO layer (Phase 1), propagating layer tags through findings, or including layer metadata in output |
What ships with it
7 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
- references/attack-chain-patterns-shared.md 14 KB
- references/finding-format-shared.md 17 KB
- references/maestro-agentic-patterns-shared.md 33 KB
- references/maestro-layers-shared.md 8.0 KB
- references/nist-ai-rmf-mapping.md 17 KB
- references/severity-bands-shared.md 4.9 KB
- references/stride-categories-shared.md 6.8 KB
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 · 40 lines · 56 tokens per session scan A 8d529d20137a
tachi-shared is a skill published in the GitHub repository davidmatousek/tachi (94 stars, last pushed 4d ago), licensed Apache-2.0. It adds 56 tokens to every session and 724 once invoked, about $0.0002 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 2026-09-03.
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