release: 1.13.0

[stainless-app]

Automated Release PR

1.13.0 (2026-05-23)

Full Changelog: v1.12.0...v1.13.0

Features

• add /v1/metadata/user [LET-6845] (a56acb7)
• add /v1/runs/{run_id}/trace endpoint for OTEL traces (64a74a8)
• add Anthropic Opus 4.6 (fka claude-fudge-eap) model support (f023c77)
• add batch passage create and optional search query (f1cc304)
• add chatgpt oauth client for codex routing (91da4e7)
• add compaction response (2b34802)
• add conversation and conversation_messages tables for concurrent messaging (cfcd354)
• add conversation compact endpoint to SDK and add integration tests (79e7efe)
• add conversation deletion endpoint (soft delete) [LET-7286] (702cdcb)
• add conversation recompile endpoint (65f0013)
• add conversation_id filter to list runs (095e489)
• Add conversation_id filtering to message endpoints (d5cad46)
• add conversation_id to export export and compact (5ad13c5)
• add credit verification before agent message endpoints [LET-XXXX] (69f17af)
• add fireworks provider (8b536c2)
• add idempotency for conversation streaming (1398653)
• add ids to archival memory search (f7eaf79)
• add log probabilities from OpenAI-compatible servers (4575559)
• add message id filter to conversation forks (47cfba4)
• add message_types filter to list messages endpoint (da8ad59)
• add messages + passages to stainless.yml (44aac08)
• add msg id to search endpoint response (43669d7)
• add non-streaming option for conversation messages (06e1802)
• add order_by and order params to /v1/conversations list endpoin… (921f424)
• add override_model support for agent file import (d2bf995)
• add override_model to message endpoints (05863cc)
• add pagination config for list agent files (a95c0df)
• add pagination configuration for list batch message endpoint (d5a8165)
• add PATCH route for updating conversation summary (428a171)
• add pending approval field on agent state (7ddc612)
• add provider trace backend abstraction for multi-backend telemetry (4505c2f)
• add recompile system endpoint to Stainless SDK (40d9492)
• add request-id for steps [LET-6587] (e8e8768)
• add retrieve message endpoint and to client sdk (30833c7)
• add retrieve_file endpoint to get file content (db16acf)
• Add self-summarization and dropping tool returns as options for compaction (ac37637)
• add seq id to error chunks (f8f723e)
• add SGLang support (73cb106)
• add stainless pagination for identities (65eef2e)
• add strict tool calling setting [LET-6902] (7919066)
• add tags support to blocks (d84042c)
• add telemetry source identifier (35c30c6)
• add template rollback endpoint [LET-7423] (7fbbc3b)
• add ToolReturnCreate to MessageCreateParams [LET-7366] (f870fce)
• add xhigh opus 4.7 (13053eb)
• add zai provider support (0df53e4)
• allow client-side tools to be specified in request (2c95b29)
• allow for configuration compaction and return message delta (203f65e)
• allow for conversation-level isolation of blocks (0938de1)
• allow users to specify via query to stip messages [LET-7392] (d0bc48a)
• api: api update (fa185df)
• cap v1 limit query params (b5edad1)
• clean up block return object [LET-5784] (28e4290)
• client: add support for binary request streaming (86159cc)
• core: add conversation archive fields and filtering (d589286)
• core: add created_by_id and last_updated_by_id filters to list/count agents (dc45581)
• core: add image support in tool returns [LET-7140] (ff71c2d)
• core: add include_tool_calls param to message list endpoints (b7ed9c7)
• core: add is_hidden field to conversations for hidden forks (5f4a164)
• core: add moonshot and kimi code BYOK providers (0b0940b)
• core: add request-scoped system override for conversation messages (751739d)
• core: add tpuf cache warming for message search (a2d3bc3)
• core: allow creating hidden conversations (8818aca)
• core: restructure memFS system prompt rendering + add client_skills [LET-7760] (cc0756b)
• core: sort conversations by last_message_at (2d2a0fe)
• core: structure memory directory and block labels [LET-7336] (56a57c7)
• core: support forking the default (agent-direct) conversation (1f38887)
• crouton: add orgId, userId, Compaction_Settings and LLM_Config (4dd8752)
• Default to lightweight compaction model instead of agent's model (6921d55)
• expose agent_id to the messages search api endpoint (dadba42)
• expose conversation fork endpoint in Stainless SDK (6900b7a)
• Feat/user quota view (5322813)
• helm: M3 multi-signal HPA external metrics + behavior (dev shadow, prod disabled) (56f66ce)
• initial stlc build (830fb12)
• internal/types: support eagerly validating pydantic iterators (8d289a9)
• internal: implement indices array format for query and form serialization (c4a27c7)
• make agent_id optional in conversations list endpoint [LET-7612] (b180f3e)
• make config for mcp_servers and messages.modify nested (8d9ec52)
• make embedding_config optional on agent creation (24f083d)
• make some routes return none for sdk v1 (2c71c46)
• New prompts/defaults for sliding_window and all compaction (9ac78e2)
• parallel tool calling minimax provider [LET-7647] (a54cac8)
• query param parity for conversation messages (f0c80fe)
• re-enable schedule endpoints in stainless (5888ccc)
• readiness: M2 readiness enforcement scaffold (default OFF) (5568b66)
• Revert "feat: add strict tool calling setting [LET-6902]" (4b72833)
• strict tool calling setting (94dff06)
• support setting headers via env (f0c2ba8)

Bug Fixes

• autogenerated changes (0fe88a6)
• client: add missing f-string prefix in file type error message (cbf36eb)
• client: preserve hardcoded query params when merging with user params (ff0da42)
• core: persist conversation context window overrides (4e29e5f)
• don't need embedding model for self hosted [LET-7009] (5933091)
• ensure file data are only sent as 1 parameter (3df7d83)
• fix apis (5118ea2)
• fix summary message return for compaction (0c3f364)
• make attach/detach routes return None if sdk verion 1.0 (c8496f1)
• move conversations.compact to conversations.messages.compact (f84092c)
• remove invalid scheduled message schema reference (9d29c5b)
• remove letta ping schema override (30fe2d2)
• use async_to_httpx_files in patch method (a0095bb)
• use correct field name format for multipart file arrays (1039e5a)
• validation failure on blocks retrieve [LET-6709] (9a286d3)

Performance Improvements

• client: optimize file structure copying in multipart requests (1e73b56)
• core: reduce conversation send hot-path reads (8a7b06e)

Reverts

• undo PR #10058 system-prompt warning changes (05cdb2d)

Chores

• add letta source header (#58) (51c6027)
• add order_by param to list archives [LET-5839] (bc4b1c8)
• add scheduled message api (5a85700)
• ci: skip lint on metadata-only changes (1089986)
• ci: skip uploading artifacts on stainless-internal branches (c179828)
• deprecate identities/groups APIs and remove from SDK (e0089f9)
• format all api.md files (8f75778)
• internal: add --fix argument to lint script (5f85faa)
• internal: add request options to SSE classes (45fe3f6)
• internal: bump dependencies (0416184)
• internal: fix lint error on Python 3.14 (1fa4d75)
• internal: make test_proxy_environment_variables more resilient (0a47f8b)
• internal: make test_proxy_environment_variables more resilient to env (76c0a50)
• internal: more robust bootstrap script (074fe85)
• internal: reformat pyproject.toml (d9a6109)
• internal: remove mock server code (60c3a35)
• internal: update actions/checkout version (0b206d0)
• internal: update gitignore (3d4023a)
• mark agent.messages.stream endpoint as deprecated (d1bbf3f)
• rename update methods to modify in stainless (6be374c)
• speedup initial import (a4a4f90)
• update mock server docs (ce42220)
• update placeholder string (7142275)
• use main branch in sdk repos (b71fff8)

Documentation

• add more examples (2c9bba3)

Refactors

• core: remove built-in multi-agent tools (c120257)
• hard-deprecate isolated conversation blocks (ed0a3d4)
• stop creating new isolated conversation blocks (aa75f2a)

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