ci: add Stainless SDK build workflow

[declan-scale]

Summary

Adds a Stainless SDK build workflow that runs whenever agentex/openapi.yaml changes. The committed spec is the source of truth (kept fresh by the openapi-spec CI job and the agentex-openapi-spec pre-commit hook from #220), so the workflow reads it directly via git history at PR base and head SHAs — no in-CI spec generation, no submodule gymnastics.

Why here instead of scaleapi/agentex

SDK preview comments now land on the PR that actually changed the API, so contributors see "did this break the SDK?" before merging — not after a downstream submodule bump. Replaces the more complex workflow proposed in scaleapi/agentex#342, which I'll close in favor of this.

Test plan

• Trigger a no-op spec change on this PR (or a follow-up) to confirm Stainless posts a preview build comment
• After merge, confirm pushes that change agentex/openapi.yaml produce a Stainless merge build

Greptile Summary

• Adds a new .github/workflows/stainless.yml workflow that triggers Stainless SDK preview builds on PRs touching agentex/openapi.yaml and merge builds on pushes to main, using a sparse full-history checkout so the action can compare base and head spec versions without submodule complexity.
• The concurrency block uses cancel-in-progress: true with a github.ref-based group; for push events to main this can silently drop intermediate merge builds (already flagged in an existing review thread).
• fail_on: fatal means only fatal Stainless validation errors will fail the job — schema warnings and non-fatal issues pass silently.

Confidence Score: 4/5

Safe to merge with minor concerns; the concurrency issue on main was already flagged and the workflow is otherwise well-structured.

No new P0/P1 issues beyond the already-flagged cancel-in-progress concern. The workflow is minimal, uses a pinned action SHA, appropriate OIDC permissions, and efficient sparse checkout. Score capped at 4 due to the outstanding P1 in the existing thread.

No files require special attention beyond the concurrency block in .github/workflows/stainless.yml.

Important Files Changed

Filename	Overview
.github/workflows/stainless.yml	New CI workflow for Stainless SDK builds; concurrency cancel-in-progress issue on main already flagged; fail_on: fatal may silently pass non-fatal SDK schema issues.

Sequence Diagram

sequenceDiagram
    participant GH as GitHub
    participant WF as stainless.yml workflow
    participant Checkout as actions/checkout@v6
    participant Stainless as stainless-api/build action

    GH->>WF: pull_request (openapi.yaml changed)
    WF->>Checkout: sparse-checkout agentex/openapi.yaml, fetch-depth: 0
    Checkout-->>WF: full history + sparse tree
    WF->>Stainless: org=sgp, project=agentex-sdk, oas_path, fail_on=fatal
    Stainless-->>GH: Post SDK preview comment on PR

    GH->>WF: push to main (openapi.yaml changed)
    WF->>Checkout: sparse-checkout agentex/openapi.yaml, fetch-depth: 0
    Checkout-->>WF: full history + sparse tree
    WF->>Stainless: org=sgp, project=agentex-sdk, oas_path, fail_on=fatal
    Stainless-->>GH: Trigger Stainless merge build (SDK publish)

Loading

_{Reviews (3): Last reviewed commit: "remove dummy commit" | Re-trigger Greptile}

[github-actions]

✱ Stainless preview builds

No changes were made to the SDKs.

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Last updated: 2026-05-05 19:42:20 UTC