Borrowing it
Nothing to install: this file belongs to aspenkit/aspens. 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/aspenkit/aspens/main/.agents/skills/claude-runner/SKILL.mdgit clone --depth 1 https://github.com/aspenkit/aspensWrote 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/aspenkit/aspens/claude-runner)<a href="https://agentmods.dev/skills/aspenkit/aspens/claude-runner"><img src="https://agentmods.dev/badge/skills/aspenkit/aspens/claude-runner/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/aspenkit/aspens/claude-runner"><img src="https://agentmods.dev/badge/skills/aspenkit/aspens/claude-runner.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 | $0.00036 | $0.01742 |
| Opus 5.5 | $0.00014 | $0.00697 |
| Sonnet 5.5 | $0.00007 | $0.00348 |
| Haiku 4.5 | $0.00004 | $0.00174 |
Grade A, and why
claude-runner 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 — 58 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are working on the CLI execution layer — the bridge between assembled prompts and the claude -p / codex exec CLIs, plus skill file I/O.
Key Concepts
- Stream-JSON protocol (Claude):
runClaude()always passes--verbose --output-format stream-json. Output is NDJSON:type: 'result'has final text + usage;type: 'assistant'has text/tool_use blocks;type: 'user'has tool_result blocks. - JSONL protocol (Codex):
runCodex()spawnscodex exec --json --sandbox read-only --ephemeral. The--ask-for-approval neverflag is conditionally included based on capability detection (see below). Prompt is passed via stdin ('-'placeholder arg) to avoid shell arg length limits. Stdin write happens after event handlers are attached so fast failures are captured. Events:item.completed/item.updatedwith normalized types. - Codex capability detection:
getCodexExecCapabilities()(internal, cached) runscodex exec --helpand checks if--ask-for-approvalappears in the help text. Result is cached in module-levelcodexExecCapabilitiesvariable. If the help check fails (e.g., codex not installed), capabilities default to{ supportsAskForApproval: false }.runCodex()only adds--ask-for-approval neverwhensupportsAskForApprovalis true. - Unified routing:
runLLM(prompt, options, backendId)is the shared entry point — dispatches torunClaude()orrunCodex()based onbackendId. Exported fromrunner.jsso command handlers no longer need local routing helpers. - Codex internals (private):
normalizeCodexItemType()converts PascalCase/kebab-case to snake_case.collectCodexText()recursively extracts text from nested event content. Both are internal to runner.js. - Prompt templating:
loadPrompt(name, vars)resolves{{partial-name}}fromsrc/prompts/partials/first, then substitutes{{varName}}fromvars. Target-specific vars (skillsDir,skillFilename,instructionsFile,configDir) are passed by command handlers. - File output parsing: Primary:
<file path="...">content</file>XML tags. Fallback:<!-- file: path -->comment markers.parseFileOutput(output, allowedPaths)accepts optional{ dirPrefixes, exactFiles }to override default allowed paths. - Path sanitization:
sanitizePath(rawPath, allowedPaths)(internal) blocks..traversal, absolute paths. Defaults:.claude/prefix +AGENTS.mdexact. Multi-target callers pass expanded allowed paths viagetAllowedPaths()fromtarget.js. - Validation:
validateSkillFiles()checks for truncation (XML tag collisions), missing frontmatter, missing sections, bad file path references. - Skill rules generation:
extractRulesFromSkills()reads all skills viaskill-reader.js, producesskill-rules.json(v2.0) with file patterns, keywords, and intent patterns. - Domain patterns:
generateDomainPatterns()converts file patterns to bashdetect_skill_domain()function usingBEGIN/ENDmarkers. - Trigger parsing precedence:
parseTriggersFrontmatter(content)returns{ filePatterns, keywords, alwaysActivate }parsed from atriggers:block in YAML frontmatter (supports block lists, inline arrays, andalwaysActivate: truefor the base skill); returnsnullwhen notriggers:key exists.parseActivationPatternsandparseKeywordsprefer this frontmatter when present and fall back to legacy## Activation/Keywords:line parsing for older skills. - Settings merge:
mergeSettings()merges aspens hook config into existingsettings.json. Detects aspens-managed hooks byASPENS_HOOK_MARKERS(skill-activation-prompt,graph-context-prompt,post-tool-use-tracker,save-tokens-statusline,save-tokens-prompt-guard,save-tokens-precompact). Also handlesstatusLinemerging — replaces existing statusLine only if the current one is aspens-managed (detected byisAspensHook), preserving user-custom statusLine configs. After merging hooks,dedupeAspensHookEntries()removes duplicate aspens-managed entries per event type. - Directory-scoped writes:
writeTransformedFiles()handles files outside.claude/(e.g.,src/billing/AGENTS.md) with explicit path allowlist — onlyAGENTS.md,AGENTS.mdexact files and.claude/,.agents/,.codex/prefixes are permitted. findSkillFilesmatching: Only matches the exactskillFilename(e.g.,skill.mdorSKILL.md), not arbitrary.mdfiles in the skills directory.
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 · 58 lines · 36 tokens per session scan A 2f2301fbdc5d
claude-runner is a skill published in the GitHub repository aspenkit/aspens (103 stars, last pushed 1mo ago), licensed MIT. It adds 36 tokens to every session and 1,742 once invoked, about $0.0001 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 2026-08-30.
Other skills, from other repositories
do
Work a SpecWeave increment task by task - claim, implement inside its Files, test, commit, done with evidence - alone, unattended or in lanes, then close. Use for "implement", "continue", "auto".
handoff
Hand work to another tool, account or machine and pick it up there, in two words. Use when the user says "hand off", "hand off all", "out of tokens", "switching accounts", "pick up" or "continue".
sw-do
Work a SpecWeave increment task by task - claim, implement inside its Files, test, commit, done with evidence - alone, unattended or in lanes, then close. Use for "implement", "continue", "auto".
sw-handoff
Hand work to another tool, account or machine and pick it up there, in two words. Use when the user says "hand off", "hand off all", "out of tokens", "switching accounts", "pick up" or "continue".
increment
Plan work as a SpecWeave increment - one spec.md with Problem, Scope, numbered ACs, Approach and Tasks - before writing code. Use for "plan a feature", "new increment", "let's build X".
review
Adversarial review of an increment before it ships, by a fresh context or another model family; every finding cites path:line and is re-verified. Use for "review", "qa", "critique this".