Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/Everyone-Needs-A-Copilot/claude-copilotnpx agentmods add skills/everyone-needs-a-copilot/claude-copilot/link-validationWrote 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/everyone-needs-a-copilot/claude-copilot/link-validation)<a href="https://agentmods.dev/skills/everyone-needs-a-copilot/claude-copilot/link-validation"><img src="https://agentmods.dev/badge/skills/everyone-needs-a-copilot/claude-copilot/link-validation/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/everyone-needs-a-copilot/claude-copilot/link-validation"><img src="https://agentmods.dev/badge/skills/everyone-needs-a-copilot/claude-copilot/link-validation.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 | $0.01038 |
| Opus 5.5 | $0.00022 | $0.00415 |
| Sonnet 5.5 | $0.00011 | $0.00208 |
| Haiku 4.5 | $0.00006 | $0.00104 |
Grade A, and why
link-validation 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 — 147 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Link Validation
Validate markdown links and cross-references to ensure documentation integrity.
Purpose
Broken links in knowledge-copilot waste Claude's time and tokens. This skill finds and fixes broken internal links, missing anchors, and incorrect cross-references.
Link Types to Validate
| Type | Pattern | Example |
|---|---|---|
| Relative file | [text](./path.md) |
[Overview](./00-overview.md) |
| Anchor | [text](#heading) |
[Setup](#installation) |
| File + anchor | [text](./file.md#section) |
[Auth](./60-security.md#auth) |
| Parent path | [text](../other/file.md) |
[Index](../00-INDEX.md) |
| Absolute (external) | https://... |
Skip or warn |
Procedure
1. Find All Markdown Files
find . -name "*.md" -type f -not -path "./_archive/*"
2. Extract Links from Each File
Use grep to find markdown links:
grep -oE '\[([^\]]+)\]\(([^\)]+)\)' file.md
3. Categorize Links
For each link:
- External (starts with
http): Skip or optionally validate - Anchor only (
#heading): Validate heading exists in same file - Relative file: Resolve path and check file exists
- File + anchor: Check both file and heading exist
4. Validate Internal Links
For relative paths:
# From the file's directory, check if target exists
target_file="resolved/path/to/target.md"
if [ -f "$target_file" ]; then
echo "OK: $target_file"
else
echo "BROKEN: $target_file"
fi
5. Validate Anchors
Anchors should match headings (lowercase, hyphens for spaces):
# Extract headings from target file
grep -E '^#{1,6} ' target.md | sed 's/^#* //' | tr '[:upper:]' '[:lower:]' | sed 's/ /-/g'
6. Attempt Auto-Fix
For broken links, search for likely correct targets:
| Broken Link | Search Strategy |
|---|---|
./old-name.md |
Find files with similar names |
#old-heading |
Find similar headings in file |
../wrong/path.md |
Search for filename in other directories |
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 · 147 lines · 56 tokens per session scan A a1c34a2a181f
link-validation is a skill published in the GitHub repository Everyone-Needs-A-Copilot/claude-copilot (14 stars, last pushed yesterday), licensed MIT. It adds 56 tokens to every session and 1,038 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 2026-09-04.
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