context-os: Skill for Claude Code

.claude/skills/epistemic-context-grounding/SKILL.md

epistemic-context-grounding is a skill for Claude Code from jacob-dietle/context-os. It costs 50 tokens per session (3,427 once invoked), scanned A, original, MIT.

A pre-design check that grounds implementation decisions in the documentation and established knowledge of an unfamiliar subject area.

In plain words
What is it for?
Use it before designing software that involves unfamiliar concepts, data formats, parsing, or outside services, so assumptions can be stated and checked.
Why use it?
It reduces the risk of building the wrong solution because important domain rules, assumptions, or existing guidance were overlooked.

Skill for Claude Code

Written for Claude Code: installed under .claude/. Also seen: mentions CLAUDE.md.

This is jacob-dietle/context-os's own configuration. It tells Claude Code how to work on context-os itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything context-os configures →

Reuse

Borrowing it

Nothing to install: this file belongs to jacob-dietle/context-os. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/jacob-dietle/context-os/main/.claude/skills/epistemic-context-grounding/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/jacob-dietle/context-os

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 epistemic-context-grounding

README.md
[![agentmods](https://agentmods.dev/badge/skills/jacob-dietle/context-os/epistemic-context-grounding/github.svg)](https://agentmods.dev/skills/jacob-dietle/context-os/epistemic-context-grounding)
Your own site
<a href="https://agentmods.dev/skills/jacob-dietle/context-os/epistemic-context-grounding"><img src="https://agentmods.dev/badge/skills/jacob-dietle/context-os/epistemic-context-grounding/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.

agentmods 80×15 button for epistemic-context-grounding

Your own site · 80×15
<a href="https://agentmods.dev/skills/jacob-dietle/context-os/epistemic-context-grounding"><img src="https://agentmods.dev/badge/skills/jacob-dietle/context-os/epistemic-context-grounding.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 50 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,427 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 4 findings, up to medium

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • medium Excessive Agency · line 109
    Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.
    Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
  • medium Excessive Agency · line 298
    Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.
    Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
  • medium Excessive Agency · line 300
    Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.
    Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
  • medium Excessive Agency · line 492
    Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.
    Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
How audits are shown
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 5.1 $0.00050 $0.03427
Opus 5 $0.00025 $0.01714
Sonnet 5 $0.00010 $0.00685
Haiku 4.5 $0.00005 $0.00343

Measured 11d ago against content hash 37d2e9b1b124, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

epistemic-context-grounding 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 11d 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.

.claude/skills/epistemic-context-grounding/SKILL.md · 507 lines

How it starts

The opening of the file, as written. The whole thing — 507 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Epistemic Context Grounding

Methodology for grounding implementation decisions in domain knowledge through context sensitivity assessment, assumption enumeration, and falsifiability checking.

Why This Matters

The most common cause of wasted effort in AI-assisted work isn't bad code - it's building the wrong thing because you didn't check what documentation already describes the domain. A 2-5 minute grounding check prevents hours of rework.

When to Use This Skill

Apply this skill when:

  • Starting implementation work on unfamiliar domain
  • Task involves parsing, data models, or external integrations
  • About to design a solution (BEFORE context-gap-analysis)
  • Uncertainty exists about what documentation describes the domain

Do NOT use for:

  • Simple bug fixes with obvious root cause
  • Tasks where domain is already loaded in context
  • Pure exploration/research (no implementation planned)
  • When canonical docs were already read this session

Core Principles

1. Context Sensitivity Assessment

Classify task before designing:

LOW CONTEXT SENSITIVITY:
- Task is bounded, clear outcome
- Domain well-known (basic CRUD, standard patterns)
- Example: "Add a button to the UI"

HIGH CONTEXT SENSITIVITY:
- Task involves parsing, data formats, integrations
- Domain has canonical specs/docs
- Example: "Fix data pipeline" -> needs format knowledge

The formula: (Model : Scenario) * Context -> Output

Where:

  • Model = Claude's capabilities
  • Scenario = The specific task
  • Context = Domain knowledge provided
  • Output = Quality of solution

For HIGH context sensitivity tasks, missing context dramatically reduces output quality. For LOW context sensitivity tasks, context has minimal impact.

See references/context-sensitivity-model.md for full framework.

2. Domain Knowledge Query (Graph Traversal)

Search for specs, not just code:

SEARCH ORDER (adapt to your context OS structure):
1. specs/canonical/*.md       - Blessed architecture docs
2. specs/{project}/*.md       - Project-specific specs
3. **/CLAUDE.md               - Navigation guides
4. **/README.md               - Component documentation
5. knowledge_base/**/*.md     - Knowledge graph nodes

Read the full file on GitHub · 507 lines

Files

What ships with it

3 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.

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. 11d ago First seen · 507 lines · 50 tokens per session scan A 37d2e9b1b124

Subscribe to this mod's changes

epistemic-context-grounding is a skill published in the GitHub repository jacob-dietle/context-os (108 stars, last pushed 28d ago), licensed MIT. It adds 50 tokens to every session and 3,427 once invoked, about $0.0003 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.

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