Allow configurable model once available upstream

[strawgate]

Once github/gh-aw#17265 merges upstream let's make the model configurable

[github-actions]

TL;DR: this should be implemented, but only after upstream github/gh-aw#17265 / github/gh-aw#17296 lands; today all workflow source files use hardcoded engine.model values and expose no model input.

Recommendation

Proceed with a follow-up implementation once upstream support is merged and released, by adding a workflow_call model input (with workflow-specific defaults) and wiring engine.model to $\{\{ inputs.model }} across gh-aw workflow sources.

Findings

• Current workflow sources hardcode model in frontmatter, e.g.:
  • .github/workflows/gh-aw-issue-triage.md:11-13
  • .github/workflows/gh-aw-pr-review.md:14-16
  • .github/workflows/gh-aw-upgrade-check.md:11-14 (uses claude-opus-4.6)
• workflow_call inputs currently include fields like additional-instructions, setup-commands, etc., but no model input (example: .github/workflows/gh-aw-issue-triage.md:17-33).
• Workflow READMEs do not document a model caller input (example table: gh-agent-workflows/issue-triage/README.md:25-31; also gh-agent-workflows/pr-review/README.md:25-33).
• Caller examples currently only pass secrets and optional existing inputs, no model passthrough (e.g. gh-agent-workflows/issue-triage/example.yml:13-17, gh-agent-workflows/pr-review/example.yml:12-18).
• Upstream status:
  • github/gh-aw#17265 is open and describes why expression-based model config is currently blocked.
  • github/gh-aw#17296 is open draft/WIP to support env-var-backed model passing for expressions.

Verification

I ran repository checks to confirm current state:

$ cd /home/runner/work/ai-github-actions/ai-github-actions && echo "model lines in workflow sources: $(grep -R '^[[:space:]]*model:' .github/workflows/gh-aw-*.md | wc -l)" && echo "workflows using inputs.model expression: $(grep -R '\$\{\{ inputs.model }}' .github/workflows/gh-aw-*.md | wc -l)" && echo "workflow READMEs documenting model input row: $(grep -R -F '| `model` |' gh-agent-workflows/*/README.md | wc -l)"
model lines in workflow sources: 31
workflows using inputs.model expression: 0
workflow READMEs documenting model input row: 0

Detailed Action Plan

1. Wait for upstream support to merge/release (github/gh-aw#17265, github/gh-aw#17296), then bump GH_AW_VERSION in Makefile.
2. In each source workflow (.github/workflows/gh-aw-*.md), add a workflow_call input:
   • model (string, required: false)
   • default should preserve existing per-workflow behavior (e.g., gpt-5.3-codex for most, claude-opus-4.6 for gh-aw-upgrade-check.md).
3. Replace static engine.model literals with $\{\{ inputs.model }} in those same files.
4. Update docs to match caller behavior:
   • standard inputs section in docs/workflows/gh-agent-workflows.md:88-96
   • per-workflow input tables in gh-agent-workflows/*/README.md.
5. Update selected gh-agent-workflows/*/example.yml files to show an optional with.model override example.
6. Run make compile and make lint to regenerate lock workflows and validate.
7. Add a focused regression check to ensure compiled workflows contain caller-expression model wiring instead of hardcoded literals.

Related Items

Type	Link	Relevance
Issue	#232	This request
Upstream issue	github/gh-aw#17265	Blocking compiler/runtime behavior for expression-based model configuration
Upstream PR	github/gh-aw#17296	Draft implementation of model env-var handling
File	.github/workflows/gh-aw-issue-triage.md:11-33	Hardcoded model + no model input
File	.github/workflows/gh-aw-upgrade-check.md:11-14	Alternate default model requiring preservation
File	docs/workflows/gh-agent-workflows.md:88-96	Standard input docs that need model entry
File	gh-agent-workflows/issue-triage/README.md:25-31	Workflow input table currently lacks model

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