companion

companion is a skill for Claude Code, Codex from The-Vibe-Company/companion. It costs 61 tokens per session (18,619 once invoked), scanned A, original, MIT.

A workflow for managing local coding-agent skill packages with Companion, a service for validating, publishing, updating, installing, and auditing them.

In plain words
What is it for?
Validating or publishing skills, checking versions, resolving dependencies, managing configuration and state tables, installing updates, and auditing skills.
Why use it?
It helps keep skill versions, dependencies, configuration, secrets, and stored state under control. It also separates local skill management from the lifecycle of hosted companions.

Skill for Claude CodeCodex

Written for Claude Code and Codex: allowed-tools in frontmatter, but also reads ~/.codex or $CODEX_HOME. Also seen: reads .claude/ paths; mentions Claude Code; mentions Codex.

Needs its repository: it reads a path above its own folder, which exists only inside the repository. The line is cd <skill-folder> && zip -r -q ../skill.zip . \.

Good fit Validating or publishing skills, checking versions, resolving dependencies, managing configuration and state tables, installing updates, and auditing skills.

Compare 6 skills from other repositories ↓
About the project

Companion is a self-hosted, multi-tenant hub for managing personal and organizational SKILL.md libraries used by coding agents. It is for organizations that need to store, validate, version, share, install, update, and synchronize agent skills, with optional named companions that have persistent workspaces and chats. The catalogue skills, agents, and instructions are resources managed or used within this workflow.

The-Vibe-Company/companion · 2,401 stars · on GitHub · thecompanion.sh

Install

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.

Clone the repo
git clone --depth 1 https://github.com/The-Vibe-Company/companion
agentmods
npx agentmods add skills/the-vibe-company/companion/skill

Made for: Claude Code, Codex.

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 companion

README.md
[![agentmods](https://agentmods.dev/badge/skills/the-vibe-company/companion/skill/github.svg)](https://agentmods.dev/skills/the-vibe-company/companion/skill)
Your own site
<a href="https://agentmods.dev/skills/the-vibe-company/companion/skill"><img src="https://agentmods.dev/badge/skills/the-vibe-company/companion/skill/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 companion

Your own site · 80×15
<a href="https://agentmods.dev/skills/the-vibe-company/companion/skill"><img src="https://agentmods.dev/badge/skills/the-vibe-company/companion/skill.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 61 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 18,619 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: 25 findings, up to high

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 →

  • high Rogue Agent · line 3
    Skill modifies its own code, configuration, or behavior at runtime. Self-modification enables an agent to escalate privileges, disable safety constraints, or install persistent backdoors.
    Fix: Prevent the skill from modifying its own code, SKILL.md, or configuration files. Treat skill files as read-only at runtime.
  • high Rogue Agent · line 14
    Skill modifies its own code, configuration, or behavior at runtime. Self-modification enables an agent to escalate privileges, disable safety constraints, or install persistent backdoors.
    Fix: Prevent the skill from modifying its own code, SKILL.md, or configuration files. Treat skill files as read-only at runtime.
  • high Privilege Escalation · line 107
    Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.
    Fix: Remove references to credential paths. Use environment variables or secrets managers. For docs, use placeholder paths (e.g., /path/to/config). Never load .env or token files in production code paths.
  • high Privilege Escalation · line 137
    Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.
    Fix: Remove references to credential paths. Use environment variables or secrets managers. For docs, use placeholder paths (e.g., /path/to/config). Never load .env or token files in production code paths.
  • high Privilege Escalation · line 158
    Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.
    Fix: Remove references to credential paths. Use environment variables or secrets managers. For docs, use placeholder paths (e.g., /path/to/config). Never load .env or token files in production code paths.
  • high Privilege Escalation · line 168
    Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.
    Fix: Remove references to credential paths. Use environment variables or secrets managers. For docs, use placeholder paths (e.g., /path/to/config). Never load .env or token files in production code paths.
  • high Privilege Escalation · line 169
    Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.
    Fix: Remove references to credential paths. Use environment variables or secrets managers. For docs, use placeholder paths (e.g., /path/to/config). Never load .env or token files in production code paths.
  • high Privilege Escalation · line 193
    Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.
    Fix: Remove references to credential paths. Use environment variables or secrets managers. For docs, use placeholder paths (e.g., /path/to/config). Never load .env or token files in production code paths.
  • high Rogue Agent · line 281
    Skill modifies its own code, configuration, or behavior at runtime. Self-modification enables an agent to escalate privileges, disable safety constraints, or install persistent backdoors.
    Fix: Prevent the skill from modifying its own code, SKILL.md, or configuration files. Treat skill files as read-only at runtime.
  • high Tool Misuse · line 1292
    Tool parameters are crafted to achieve unintended or unsafe behavior. Parameter abuse can bypass intended safety checks (e.g. shell=True, --force, dangerous glob patterns).
    Fix: Validate all tool parameters against an allowlist. Reject dangerous parameter values (shell=True, --force, -rf /) and use safe defaults.
  • high Tool Misuse · line 1327
    Tool parameters are crafted to achieve unintended or unsafe behavior. Parameter abuse can bypass intended safety checks (e.g. shell=True, --force, dangerous glob patterns).
    Fix: Validate all tool parameters against an allowlist. Reject dangerous parameter values (shell=True, --force, -rf /) and use safe defaults.
  • high Tool Misuse · line 1328
    Tool parameters are crafted to achieve unintended or unsafe behavior. Parameter abuse can bypass intended safety checks (e.g. shell=True, --force, dangerous glob patterns).
    Fix: Validate all tool parameters against an allowlist. Reject dangerous parameter values (shell=True, --force, -rf /) and use safe defaults.
  • high Rogue Agent · line 1330
    Skill modifies its own code, configuration, or behavior at runtime. Self-modification enables an agent to escalate privileges, disable safety constraints, or install persistent backdoors.
    Fix: Prevent the skill from modifying its own code, SKILL.md, or configuration files. Treat skill files as read-only at runtime.
  • medium Rogue Agent · line 26
    Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.
    Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
  • medium Excessive Agency · line 35
    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 Rogue Agent · line 316
    Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.
    Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
  • medium Rogue Agent · line 563
    Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.
    Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
  • medium Agent Snooping · line 574
    Skill enumerates or reads other installed skills. Access to other skills' SKILL.md files or the skills directory reveals prompt instructions, capabilities, and secrets that should be invisible to peer skills.
    Fix: Remove all code or instructions that list or read other skills' files or directories. Skills should operate independently; cross-skill access is a privilege escalation.
  • medium Agent Snooping · line 578
    Skill enumerates or reads other installed skills. Access to other skills' SKILL.md files or the skills directory reveals prompt instructions, capabilities, and secrets that should be invisible to peer skills.
    Fix: Remove all code or instructions that list or read other skills' files or directories. Skills should operate independently; cross-skill access is a privilege escalation.
  • medium Rogue Agent · line 750
    Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.
    Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
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 $0.00061 $0.18619
Opus 5 $0.00030 $0.09309
Sonnet 5 $0.00012 $0.03724
Haiku 4.5 $0.00006 $0.01862

Measured 3d ago against content hash 366c5428bedb, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

companion 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 3d ago.

The scan reads SKILL.md. This mod also ships 19 executable files (scripts/bootstrap_integrity.py, scripts/bootstrap_update.py, scripts/bootstrap.py, …), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

packages/companion-skill/skill/SKILL.md · 1,346 lines

How it starts

The opening of the file, as written. The whole thing — 1,346 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Companion

This skill lets you manage the skills on this machine and keep them in sync with a Companion workspace: validate a skill, publish it, push an update, manage its pinned public release, and check whether everything is current. Agent Auth is the default programmatic identity. Run the mandatory Companion self-update check once at the first Companion invocation in a conversation, and always confirm a change with the user before anything is published.

Companion is a Skills Hub. External agents use delegated Agent Auth to manage portable skill packages, secrets, and declared Skill Databases. The control plane never executes package scripts.

Configuration

You need two non-secret values, supplied by the web app's Use with an agent prompt:

  • COMPANION_API_URL — the workspace API base, e.g. https://companion.acme.dev/v1.
  • COMPANION_WORKSPACE_ID — the Companion workspace id (organizations.id), used to key local credentials and install inventory.
  • COMPANION_DELEGATION_TOKEN — optional short-lived child PAT for a non-interactive workspace. If present, the client uses it directly and does not read credentials.json or start connect/device approval. COMPANION_API_URL and COMPANION_WORKSPACE_ID are then both mandatory.
  • COMPANION_DELEGATION_TARGET_ID — optional explicit runtime target binding. It must match the id recorded at issuance and is sent only in X-Companion-Delegation-Target.
  • an Agent Auth reference { issuer, agentId } for that workspace. The bundled client discovers the instance, dynamically registers the host, opens the device-approval page, and requests short-lived JWTs when a capability is needed.

The first connection requests only skills:read constrained to the exact workspace id. The first write requests skills:write; the first Secrets read or write requests secrets:read or secrets:write; Skill Database descriptions and queries request database:read, while DML requests database:write. Database write includes read because DML can observe state through predicates, subqueries, conflict handling, and returned rows. Approvals are persistent until revoked, while every request JWT lasts 60 seconds. Never request a broader workspace constraint.

Read the full file on GitHub · 1,346 lines

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. 3d ago Changed · -94 lines 366c5428bedb
  2. 6d ago Changed · +36 lines bab25eacf927
  3. 9d ago First seen · 1,404 lines · 61 tokens per session scan A 708df5e1b554

Subscribe to this mod's changes

companion is a skill published in the GitHub repository The-Vibe-Company/companion (2,401 stars, last pushed 3d ago), licensed MIT. It adds 61 tokens to every session and 18,619 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 2026-09-02.

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