Codex: no web search tool for Responses Lite models (openai-proxy provider lacks supports_standalone_web_search) #67148

Codex: no web search tool for Responses Lite models

With the Codex engine, tools.web-search + network.hosted-web gives a Responses Lite model (e.g. gpt-5.6-terra) no search tool. The agent says web search is unavailable, and the log has no web_search item.

The docs make no exception for models or providers (engines/codex.md, reference/network.md).

Versions: gh-aw v0.91.5, AWF v0.28.44, codex 0.159.3.

engine:
  id: codex
  model: gpt-5.6-terra
network:
  allowed: [defaults]
  hosted-web:
    allowed: [docs.example.com]
tools:
  web-search:

Analysis

This analysis was done with an agent and checked against the source at the tags above.

1. codex gives Responses Lite models no hosted web_search tool. Their only search tool is the standalone web.run (spec_plan.rs).
2. web.run is registered only if the provider is OpenAI, uses actor authorization, or sets supports_standalone_web_search (extension.rs).
3. The generated openai-proxy provider meets none of these (codex_config.go). This is still the case in v0.91.6 and on main.

Setting the flag through engine.config makes the agent call web.run:

[model_providers.openai-proxy]
supports_standalone_web_search = true

The calls then fail at the AWF api-proxy with 400 codex_hosted_web_shape_invalid. That part is reported in github/gh-aw-firewall#9744.

Implementation Plan

1. Provider config. In pkg/workflow/codex_config.go, set supports_standalone_web_search = true on openai-proxy when Codex hosted web is enabled and the upstream is OpenAI.
   • This affects only Responses Lite models, because codex's StandaloneWebSearch feature is off by default.
2. max-uses. AWF rejects standalone search when max-uses is set (codex_hosted_web_max_uses_unsupported). Reject or warn about that combination at compile time instead of dropping the limit silently.
3. Tests. Add a unit test in pkg/workflow covering the flag with and without hosted-web.
4. Docs. Note the behaviour in docs/src/content/docs/engines/codex.md.
5. Finish. Run make agent-finish.

Acceptance criteria

• A Codex workflow with tools.web-search and network.hosted-web compiles to a config whose [model_providers.openai-proxy] has supports_standalone_web_search = true, and a test asserts it.
• Without hosted-web, the flag is not set.