Add custom-forward-backward and forward endpoints for RL custom losses

[dvmazur]

Summary

• Adds four new RL training operation endpoints for the custom losses feature:
  • POST /rl/training-sessions/{session_id}/operations/custom-forward-backward — submit a forward-backward pass driven by externally computed log-prob gradients
  • GET /rl/training-sessions/{session_id}/operations/custom-forward-backward/{operation_id} — poll status/result
  • POST /rl/training-sessions/{session_id}/operations/forward — submit a no-grad forward pass to retrieve per-token log-probabilities
  • GET /rl/training-sessions/{session_id}/operations/forward/{operation_id} — poll status/result
• Adds corresponding schema definitions: RL.CustomForwardBackwardBody, RL.CustomForwardBackwardOperation, RL.CustomForwardBackwardResult, RL.ForwardBody, RL.ForwardOperation, RL.ForwardResult, RL.TargetLogprobs, RL.TargetLogprobGradients
• All new schemas follow the existing RL.* naming convention and OpenAPI 3.1 style of the file

Companion PR in together-shaping: https://github.com/togethercomputer/together-shaping/pull/3333

Test plan

• Verify new path blocks render correctly in the OpenAPI viewer
• Confirm all $ref targets resolve (no dangling references)
• Check that RL.DType (referenced by RL.TargetLogprobGradients) already exists in the file — it does, at the RL.DType schema definition

🤖 Generated with Claude Code

[github-actions]

✱ Stainless preview builds for togetherai

This PR will update the togetherai SDKs with the following commit messages.

go

chore(internal): regenerate SDK with no functional changes

openapi

feat(api): add forward and custom-forward-backward operations to RL training sessions

python

chore(internal): regenerate SDK with no functional changes

terraform

chore(internal): regenerate SDK with no functional changes

typescript

chore(internal): regenerate SDK with no functional changes

Edit this comment to update them. They will appear in their respective SDK's changelogs.

✅ togetherai-openapi studio · code · diff

Your SDK build had at least one new note diagnostic, which is a regression from the base state.
generate ✅

New diagnostics (4 note)

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `post /rl/training-sessions/{session_id}/operations/custom-forward-backward`

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `get /rl/training-sessions/{session_id}/operations/custom-forward-backward/{operation_id}`

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `post /rl/training-sessions/{session_id}/operations/forward`

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `get /rl/training-sessions/{session_id}/operations/forward/{operation_id}`

✅ togetherai-go studio · code · diff

Your SDK build had at least one new note diagnostic, which is a regression from the base state.
generate ✅ → build ⏭️ (prev: build ✅) → lint ✅ → test ❗

go get github.com/stainless-sdks/togetherai-go@39b6984abe29b46bc12019699639842737cbb83f

New diagnostics (4 note)

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `post /rl/training-sessions/{session_id}/operations/custom-forward-backward`

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `get /rl/training-sessions/{session_id}/operations/custom-forward-backward/{operation_id}`

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `post /rl/training-sessions/{session_id}/operations/forward`

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `get /rl/training-sessions/{session_id}/operations/forward/{operation_id}`

✅ togetherai-python studio · code · diff

Your SDK build had at least one new note diagnostic, which is a regression from the base state.
generate ⚠️ → build ⏭️ (prev: build ✅) → lint ⏭️ (prev: lint ✅) → test ⏭️

New diagnostics (4 note)

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `post /rl/training-sessions/{session_id}/operations/custom-forward-backward`

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `get /rl/training-sessions/{session_id}/operations/custom-forward-backward/{operation_id}`

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `post /rl/training-sessions/{session_id}/operations/forward`

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `get /rl/training-sessions/{session_id}/operations/forward/{operation_id}`

✅ togetherai-typescript studio · code · diff

Your SDK build had at least one new note diagnostic, which is a regression from the base state.
generate ⚠️ → build ⏭️ (prev: build ✅) → lint ⏭️ (prev: lint ✅) → test ✅

New diagnostics (4 note)

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `post /rl/training-sessions/{session_id}/operations/custom-forward-backward`

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `get /rl/training-sessions/{session_id}/operations/custom-forward-backward/{operation_id}`

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `post /rl/training-sessions/{session_id}/operations/forward`

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `get /rl/training-sessions/{session_id}/operations/forward/{operation_id}`

✅ togetherai-terraform studio · code · diff

Your SDK build had at least one new note diagnostic, which is a regression from the base state.
generate ✅ → lint ✅ → test ✅

New diagnostics (4 note)

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `post /rl/training-sessions/{session_id}/operations/custom-forward-backward`

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `get /rl/training-sessions/{session_id}/operations/custom-forward-backward/{operation_id}`

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `post /rl/training-sessions/{session_id}/operations/forward`

💡 Endpoint/NotConfigured: Skipped endpoint because it's not in your Stainless config: `get /rl/training-sessions/{session_id}/operations/forward/{operation_id}`

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Last updated: 2026-05-11 18:57:01 UTC