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 skills add oliver-kriska/claude-elixir-phoenix --skill hexdocs-fetchergit clone --depth 1 https://github.com/oliver-kriska/claude-elixir-phoenixWrote 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/oliver-kriska/claude-elixir-phoenix/hexdocs-fetcher)<a href="https://agentmods.dev/skills/oliver-kriska/claude-elixir-phoenix/hexdocs-fetcher"><img src="https://agentmods.dev/badge/skills/oliver-kriska/claude-elixir-phoenix/hexdocs-fetcher/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/oliver-kriska/claude-elixir-phoenix/hexdocs-fetcher"><img src="https://agentmods.dev/badge/skills/oliver-kriska/claude-elixir-phoenix/hexdocs-fetcher.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 | $0.00039 | $0.00784 |
| Opus 5.5 | $0.00016 | $0.00314 |
| Sonnet 5.5 | $0.00008 | $0.00157 |
| Haiku 4.5 | $0.00004 | $0.00078 |
Grade A, and why
hexdocs-fetcher 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 — 122 lines — stays where its author put it; the contents beside it link to each section on GitHub.
HexDocs Fetcher
Efficiently fetch Elixir library documentation from hexdocs.pm using Claude Code's native WebFetch tool.
Usage
When researching libraries, use WebFetch:
# Fetch library overview
WebFetch(
url: "https://hexdocs.pm/oban",
prompt: "Extract the main documentation, including module overview, installation instructions, and key functions. Format as clean markdown."
)
# Fetch specific module docs
WebFetch(
url: "https://hexdocs.pm/phoenix_live_view/Phoenix.LiveView.html",
prompt: "Extract the module documentation including all public functions, their specs, and examples."
)
# Fetch getting started guide
WebFetch(
url: "https://hexdocs.pm/ecto/getting-started.html",
prompt: "Extract the complete getting started guide content."
)
Token Efficiency
WebFetch automatically converts HTML to markdown and extracts relevant content:
| Source | Raw HTML | With WebFetch | Benefit |
|---|---|---|---|
| HexDocs page | ~80k tokens | ~15k tokens | 80% reduction |
| Phoenix docs | ~120k tokens | ~25k tokens | 79% reduction |
| README | ~20k tokens | ~8k tokens | 60% reduction |
Integration with hex-library-researcher
When evaluating libraries, fetch docs efficiently:
# Get library overview with focused extraction
WebFetch(
url: "https://hexdocs.pm/oban",
prompt: "Extract: 1) Installation instructions 2) Main features 3) Basic usage example"
)
Common HexDocs URLs
# Library overview
https://hexdocs.pm/{library}
# Module documentation
https://hexdocs.pm/{library}/{Module}.html
https://hexdocs.pm/{library}/{Module.Submodule}.html
# Guides
https://hexdocs.pm/{library}/guides.html
https://hexdocs.pm/{library}/{guide-name}.html
# API reference
https://hexdocs.pm/{library}/api-reference.html
Prompt Strategies
Use focused prompts for better extraction:
# For API docs
prompt: "Extract all public function docs with @spec and examples"
# For guides
prompt: "Extract the complete guide content preserving code examples"
# For troubleshooting
prompt: "Extract any troubleshooting sections, common errors, and FAQs"
# For configuration
prompt: "Extract configuration options and their defaults"
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 · 122 lines · 39 tokens per session scan A e50a13ab85b2
hexdocs-fetcher is a skill published in the GitHub repository oliver-kriska/claude-elixir-phoenix (567 stars, last pushed yesterday), licensed MIT. It adds 39 tokens to every session and 784 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.
Other skills, from other repositories
craft-content-modeling
Craft CMS 5 content modeling — sections, entry types, fields, Matrix, relations, project config, and content architecture strategy. Covers choosing section types, designing entry types and field layouts, selecting field types, configuring Matrix and nested entries, relations and eager loading, and multi-site…
craftcms
Craft CMS 5 plugin and module development — extending Craft with PHP. Covers elements, element queries, services, models, records, controllers, migrations, queue jobs, console commands, field types, native fields, events, behaviors, Twig extensions, widgets, filesystems, permissions, project config, GraphQL, testing…
craft-php-guidelines
Craft CMS 5 PHP coding standards and conventions. ALWAYS load when writing, editing, reviewing, or discussing any PHP in a Craft plugin or module — even small edits. Also when running ECS, PHPStan, or scaffolding with ddev craft make. Covers: PHPDoc blocks (@author, @since, @throws chains), section headers…
craft-twig-guidelines
Twig coding standards and conventions for Craft CMS 5 templates. ALWAYS load this skill when writing, editing, or reviewing any .twig file in a Craft CMS project — even for small edits. Covers: variable naming (camelCase, no abbreviations), null handling (?? operator, ??? with empty-coalesce plugin), whitespace…
craft-pest
Testing Craft CMS 5 plugins and modules with Pest — test isolation, database safety, and the markhuot/craft-pest-core harness. ALWAYS load when writing, running, fixing, or reviewing tests for a Craft plugin or module, and whenever a suite touches a real Craft install. Covers why rollback is opt-in, tests/Pest.php +…
craft-plugin-release
Releasing Craft CMS plugins — tagging, Packagist propagation, GitHub releases, branch promotion, shared-library ordering, history rewrites. ALWAYS load when cutting, preparing, verifying, or debugging a plugin release: bumping a version, dating a changelog, creating or moving a git tag, or checking what Packagist…