Ax is a TypeScript-first programming framework for building applications with large language models through typed generation, agents, workflows, and optimization tools. It is intended for developers who want one model for LLM programs across TypeScript, Python, Java, C++, Go, Rust, and other runtimes.
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 ax-llm/ax --skill ax-cpp-refinegit clone --depth 1 https://github.com/ax-llm/axWrote 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/ax-llm/ax/ax-cpp-refine)<a href="https://agentmods.dev/skills/ax-llm/ax/ax-cpp-refine"><img src="https://agentmods.dev/badge/skills/ax-llm/ax/ax-cpp-refine/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/ax-llm/ax/ax-cpp-refine"><img src="https://agentmods.dev/badge/skills/ax-llm/ax/ax-cpp-refine.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00037 | $0.00502 |
| Opus 5.5 | $0.00015 | $0.00201 |
| Sonnet 5.5 | $0.00007 | $0.00100 |
| Haiku 4.5 | $0.00004 | $0.00050 |
Grade A, and why
ax-cpp-refine 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 yesterday.
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.
This is a copy
81% identical to ax-cpp-playbook — 20 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
What it actually says
Ax Refinement Patterns For C++
This skill helps an agent write C++ code with the generated Ax package axllm. Use the generated package API, examples, and manifests; do not import TypeScript-only APIs unless you are editing the TypeScript package.
When To Use
- Improve generated outputs with evaluator feedback or optimizer artifacts.
- Port TypeScript refinement intent into generated-language surfaces without assuming TypeScript-only helpers.
- Use generated optimizer APIs when the target package does not expose a standalone refine helper.
Package Facts
- Language: C++.
- Package:
axllm. - Package API docs:
API.mdandaxir-api.json. - Capability manifest:
axir-capabilities.json. - Runnable examples:
examples/. - Real network support: yes.
- Scripted no-key transport support: yes.
- Runtime profiles:
javascript-quickjs,python-pyodide.
Core Pattern
axllm::AxGEPA engine(reflection_client, options);
auto result = engine.optimize(request, evaluator);
Relevant API Surface
- AxGen:
axllm::ax,axllm::AxGen,axllm::run_control,axllm::AxRunControl,axllm::AxCachingFunction,axllm::set_caching_function - Optimizers:
axllm::optimize,axllm::playbook,axllm::AxPlaybook,axllm::AxBootstrapFewShot,axllm::AxGEPA,axllm::OptimizerEngine,axllm::OptimizerEvaluator
Guardrails
- Start from package examples for exact native syntax before inventing a new call shape.
- Use
provider-apiexamples only when the user explicitly has provider credentials available. - Use
no-keyexamples for deterministic local checks and provider request mapping. - Treat AxIR as the source of generated package truth: if package docs disagree with source code, update the compiler and regenerate packages.
- Do not copy repo-maintainer skills from
tools/*/skills/into user packages.
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.
- yesterday Changed 4e683abf914e
- 2d ago Changed ea2b9aedec06
- 4d ago Changed 9da9a44c1357
- 6d ago Changed 06c8fd54d1cf
- 8d ago Changed 4ca32e2c6f38
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- 13d ago Changed 7fbfa59a428d
- 19d ago Changed 5963ca0426b3
- 22d ago First seen · 45 lines · 37 tokens per session scan A abde6dc656e1
ax-cpp-refine is a skill published in the GitHub repository ax-llm/ax (2,967 stars, last pushed 2d ago), licensed Apache-2.0. It adds 37 tokens to every session and 502 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 81% identical to ax-cpp-playbook, differing in 20 lines, and is treated as a copy.
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