Codex-api

Codex-api is a skill for Claude Code, Codex from opencue/cuecards. It costs 294 tokens per session (8,698 once invoked), scanned A, original, MIT.

A reference for building applications with the Codex or Anthropic software libraries, including model calls, streaming, tools, and agents.

In plain words
What is it for?
Adding language-model features to supported projects, such as tool use, MCP connections, agent workflows, streaming responses, caching, and token counting.
Why use it?
It helps developers choose compatible models and implementation methods while avoiding provider mismatches in existing projects.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: mentions subagents; names the AskUserQuestion tool; positional $N argument.

Good fit Adding language-model features to supported projects, such as tool use, MCP connections, agent workflows, streaming responses, caching, and token counting.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/opencue/cuecards/claude-api
Install

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.

Any agent
npx skills add opencue/cuecards --skill claude-api
Clone the repo
git clone --depth 1 https://github.com/opencue/cuecards

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 Codex-api

README.md
[![agentmods](https://agentmods.dev/badge/skills/opencue/cuecards/claude-api/github.svg)](https://agentmods.dev/skills/opencue/cuecards/claude-api)
Your own site
<a href="https://agentmods.dev/skills/opencue/cuecards/claude-api"><img src="https://agentmods.dev/badge/skills/opencue/cuecards/claude-api/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 Codex-api

Your own site · 80×15
<a href="https://agentmods.dev/skills/opencue/cuecards/claude-api"><img src="https://agentmods.dev/badge/skills/opencue/cuecards/claude-api.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 294 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 8,698 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. 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: 2 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 Memory Poisoning · line 266
    Skill attempts to fill the context window with filler content, displacing legitimate instructions and safety constraints. This can degrade agent performance or bypass safety boundaries.
    Fix: Implement context-window management that detects and rejects padding or stuffing attempts. Prioritize system instructions over user-injected content.
  • medium Excessive Agency · line 328
    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 $0.00294 $0.08698
Opus 5.5 $0.00118 $0.03479
Sonnet 5.5 $0.00059 $0.01740
Haiku 4.5 $0.00029 $0.00870

Measured 2mo ago against content hash 98be174cb5ad, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

Codex-api scanned grade A with 1 finding 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 2mo 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

2. **Raw HTTP** (`curl`, `requests`, `fetch`, `httpx`, etc.) — only when the user explicitly asks for cURL/REST/raw HTTP, the project is a shell/cURL project, or the language has no official SDK.
.agents/skills/claude-api/SKILL.md · 336 lines

How it starts

The opening of the file, as written. The whole thing — 336 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Building LLM-Powered Applications with Codex

This skill helps you build LLM-powered applications with Codex. Choose the right surface based on your needs, detect the project language, then read the relevant language-specific documentation.

Before You Start

Scan the target file (or, if no target file, the prompt and project) for non-Anthropic provider markers — import openai, from openai, langchain_openai, OpenAI(, gpt-4, gpt-5, file names like agent-openai.py or *-generic.py, or any explicit instruction to keep the code provider-neutral. If you find any, stop and tell the user that this skill produces Codex/Anthropic SDK code; ask whether they want to switch the file to Codex or want a non-Codex implementation. Do not edit a non-Anthropic file with Anthropic SDK calls.

Output Requirement

When the user asks you to add, modify, or implement a Codex feature, your code must call Codex through one of:

  1. The official Anthropic SDK for the project's language (anthropic, @anthropic-ai/sdk, com.anthropic.*, etc.). This is the default whenever a supported SDK exists for the project.
  2. Raw HTTP (curl, requests, fetch, httpx, etc.) — only when the user explicitly asks for cURL/REST/raw HTTP, the project is a shell/cURL project, or the language has no official SDK.

Never mix the two — don't reach for requests/fetch in a Python or TypeScript project just because it feels lighter. Never fall back to OpenAI-compatible shims.

Never guess SDK usage. Function names, class names, namespaces, method signatures, and import paths must come from explicit documentation — either the {lang}/ files in this skill or the official SDK repositories or documentation links listed in shared/live-sources.md. If the binding you need is not explicitly documented in the skill files, WebFetch the relevant SDK repo from shared/live-sources.md before writing code. Do not infer Ruby/Java/Go/PHP/C# APIs from cURL shapes or from another language's SDK.

Read the full file on GitHub · 336 lines

Files

What ships with it

47 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. 2mo ago First seen · 336 lines · 294 tokens per session scan A 98be174cb5ad

Subscribe to this mod's changes

Codex-api is a skill published in the GitHub repository opencue/cuecards (7 stars, last pushed yesterday), licensed MIT. It adds 294 tokens to every session and 8,698 once invoked, about $0.0012 per session on Opus 5.5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Related

Codex-api compared with skills from other repositories

Codex-api next to 6 skills from other repositories
ModTypeStarsLast pushLicenceScanTokensWorks with
Codex-apiopencue/cuecardsSkill7yesterdayMITA294Claude Code, Codex
agentloop-audit-queryalibaba/loongsuite-pilotSkill239yesterdayApache-2.0A114Claude Code, Codex
loongsuite-pilot-insightalibaba/loongsuite-pilotSkill239yesterdayApache-2.0A111Claude Code, Codex
loongsuite-pilot-opsalibaba/loongsuite-pilotSkill239yesterdayApache-2.0A15Claude Code, Codex
atomic-visual-optionsdamusix/atomic-claudeSkill1155d agoMITA150Claude Code, Codex
atomic-wikidamusix/atomic-claudeSkill1155d agoMITA204Claude Code, Codex
atomic-reviewdamusix/atomic-claudeSkill1155d agoMITA63Claude Code, Codex