--- title: "Changes to Create a new tool router session" method: POST path: "/api/v3/tool_router/session" --- # Changes to Create a new tool router session `POST /api/v3/tool_router/session` > Every recorded change to this operation, newest first. ## Timeline Changed in 21 of 52 revisions. - **2026-10-22** `b83d624ab260`: 1 breaking, 1 warning - **2026-10-21** `de1396b30307`: 2 breaking, 2 info - **2026-10-19** `d7c19962d149`: 2 info - **2026-10-16** `c4ce663f967e`: 1 info - **2026-10-15** `d3f45c8da901`: 3 breaking, 12 warning, 3 info - **2026-10-14** `84a5c8e82c5b`: 2 info - **2026-10-08** `0b66fbcbc714`: 2 breaking, 6 info - **2026-10-07** `887f3a98b87b`: 2 breaking, 10 info - **2026-10-04** `3b652ab08989`: 3 info - **2026-09-30** `da0faa944f15`: 1 breaking, 1 warning, 2 info - **2026-09-23** `ccde5b3d5502`: 2 info - **2026-09-15** `e27f2d779f27`: 2 info - **2026-09-08** `2615c2178abd`: 1 info - **2026-09-02** `196b1ac21e80`: 1 info - **2026-08-31** `fe5fcbde6466`: 1 info - **2026-08-07** `df7478fc8f3b`: 1 info - **2026-08-04** `efb8b387c22c`: 3 info - **2026-07-12** `73b05c1e5119`: 9 info - **2026-05-03** `afeba73724e5`: 13 info - **2026-03-20** `1a01eea79bb9`: 1 breaking, 9 info - **2026-02-12** `881fa7b9eb11`: 2 breaking, 9 warning, 20 info ## Changes - **2026-10-22** `b83d624ab260`: 1 breaking, 1 warning - the `hooks` request property type changed from no type to `array` - removed `#/components/schemas/SessionHooks, subschema #2` from the `hooks` request property `allOf` list - **2026-10-21** `de1396b30307`: 2 breaking, 2 info - removed `subschema #1, subschema #2` from the `hooks/allOf[#/components/schemas/SessionHooks]/items/` request property `oneOf` list - added `subschema #1, subschema #2` to the `config/hooks/items/` response property `oneOf` list for the response status `201` - added `subschema #1, subschema #2` to the `hooks/allOf[#/components/schemas/SessionHooks]/items/` request property `oneOf` list - removed `subschema #1, subschema #2` from the `config/hooks/items/` response property `oneOf` list for the response status `201` - **2026-10-19** `d7c19962d149`: 2 info - added the new optional request property `hooks` - added the optional property `config/hooks` to the response with the `201` status - **2026-10-16** `c4ce663f967e`: 1 info - added the new optional request property `experimental/restrict_egress_to_composio` - **2026-10-15** `d3f45c8da901`: 3 breaking, 12 warning, 3 info - removed `subschema #1, subschema #2` from the `tags` request property `anyOf` list - removed `subschema #1, subschema #2, subschema #3` from the `toolkits` request property `anyOf` list - removed `subschema #1, subschema #2, subschema #3, subschema #4` from the `tools/additionalProperties/` request property `anyOf` list - added the new `createHint` enum value to the `config/tags/disabled/items/` response property for the response status `201` - added the new `createHint` enum value to the `config/tags/enabled/items/` response property for the response status `201` - added the new `createHint` enum value to the `config/tags/require_approval/items/` response property for the response status `201` - added the new `createHint` enum value to the `config/tools/additionalProperties/anyOf[subschema #3]/tags/disabled/items/` response property for the response status `201` - added the new `createHint` enum value to the `config/tools/additionalProperties/anyOf[subschema #3]/tags/enabled/items/` response property for the response status `201` - added the new `createHint` enum value to the `config/tools/additionalProperties/anyOf[subschema #3]/tags/require_approval/items/` response property for the response status `201` - added the new `updateHint` enum value to the `config/tags/disabled/items/` response property for the response status `201` - added the new `updateHint` enum value to the `config/tags/enabled/items/` response property for the response status `201` - added the new `updateHint` enum value to the `config/tags/require_approval/items/` response property for the response status `201` - added the new `updateHint` enum value to the `config/tools/additionalProperties/anyOf[subschema #3]/tags/disabled/items/` response property for the response status `201` - added the new `updateHint` enum value to the `config/tools/additionalProperties/anyOf[subschema #3]/tags/enabled/items/` response property for the response status `201` - added the new `updateHint` enum value to the `config/tools/additionalProperties/anyOf[subschema #3]/tags/require_approval/items/` response property for the response status `201` - added `subschema #1, subschema #2` to the `tags` request property `anyOf` list - added `subschema #1, subschema #2, subschema #3` to the `toolkits` request property `anyOf` list - added `subschema #1, subschema #2, subschema #3, subschema #4` to the `tools/additionalProperties/` request property `anyOf` list - **2026-10-14** `84a5c8e82c5b`: 2 info - added the new optional request property `instant/anyOf[subschema #2]/return_prices_in_search` - added the required property `config/instant/anyOf[subschema #2]/return_prices_in_search` to the response with the `201` status - **2026-10-08** `0b66fbcbc714`: 2 breaking, 6 info - removed `subschema #1, subschema #2, subschema #3` from the `toolkits` request property `anyOf` list - removed `subschema #1, subschema #2, subschema #3, subschema #4` from the `tools/additionalProperties/` request property `anyOf` list - added `subschema #1, subschema #2, subschema #3` to the `toolkits` request property `anyOf` list - added `subschema #1, subschema #2, subschema #3, subschema #4` to the `tools/additionalProperties/` request property `anyOf` list - added `subschema #1, subschema #2, subschema #3` to the `config/toolkits` response property `anyOf` list for the response status `201` - added `subschema #1, subschema #2, subschema #3, subschema #4` to the `config/tools/additionalProperties/` response property `anyOf` list for the response status `201` - removed `subschema #1, subschema #2, subschema #3` from the `config/toolkits` response property `anyOf` list for the response status `201` - removed `subschema #1, subschema #2, subschema #3, subschema #4` from the `config/tools/additionalProperties/` response property `anyOf` list for the response status `201` - **2026-10-07** `887f3a98b87b`: 2 breaking, 10 info - removed `subschema #1, subschema #2` from the `toolkits` request property `anyOf` list - removed `subschema #1, subschema #2, subschema #3` from the `tools/additionalProperties/` request property `anyOf` list - added the new optional request property `experimental/no_elicitation_support_fallback` - added the new optional request property `tags/anyOf[subschema #2]/require_approval` - added `subschema #1, subschema #2, subschema #3` to the `toolkits` request property `anyOf` list - added `subschema #1, subschema #2, subschema #3, subschema #4` to the `tools/additionalProperties/` request property `anyOf` list - added the optional property `config/tags/require_approval` to the response with the `201` status - added the optional property `experimental/no_elicitation_support_fallback` to the response with the `201` status - added `subschema #1, subschema #2, subschema #3` to the `config/toolkits` response property `anyOf` list for the response status `201` - added `subschema #1, subschema #2, subschema #3, subschema #4` to the `config/tools/additionalProperties/` response property `anyOf` list for the response status `201` - removed `subschema #1, subschema #2` from the `config/toolkits` response property `anyOf` list for the response status `201` - removed `subschema #1, subschema #2, subschema #3` from the `config/tools/additionalProperties/` response property `anyOf` list for the response status `201` - **2026-10-04** `3b652ab08989`: 3 info - added the new optional request property `proxy_execute` - the `workbench` request property default value changed from `{"enable":true,"enable_proxy_execution":true}` to `{"enable":true}` - added the optional property `config/proxy_execute` to the response with the `201` status - **2026-09-30** `da0faa944f15`: 1 breaking, 1 warning, 2 info - removed the required property `config/premium_usage` from the response with the `201` status - removed the request property `premium_usage` - added the new optional request property `instant` - added the required property `config/instant` to the response with the `201` status - **2026-09-23** `ccde5b3d5502`: 2 info - added the new optional request property `premium_usage` - added the required property `config/premium_usage` to the response with the `201` status - **2026-09-15** `e27f2d779f27`: 2 info - added the new optional request property `workbench/enable_tool_execution` - added the optional property `config/workbench/tool_execution_enabled` to the response with the `201` status - **2026-09-08** `2615c2178abd`: 1 info - added the new optional request property `experimental/submit_feedback` - **2026-09-02** `196b1ac21e80`: 1 info - added the non-success response with the status `404` - **2026-08-31** `fe5fcbde6466`: 1 info - added the new optional request property `experimental/fast_mode` - **2026-08-07** `df7478fc8f3b`: 1 info - added the non-success response with the status `429` - **2026-08-04** `efb8b387c22c`: 3 info - added the optional property `experimental/custom_toolkits/items/preload` to the response with the `201` status - added the optional property `experimental/custom_toolkits/items/tools/items/preload` to the response with the `201` status - added the optional property `experimental/custom_tools/items/preload` to the response with the `201` status - **2026-07-12** `73b05c1e5119`: 9 info - the endpoint scheme security `CookieAuth` was removed from the API - added the new optional request property `experimental/custom_toolkits/items/preload` - added the new optional request property `experimental/custom_toolkits/items/tools/items/preload` - added the new optional request property `experimental/custom_tools/items/preload` - added the new optional request property `experimental/link_url_overwrite` - added the new `ask_always` enum value to the request property `experimental/permissions/overrides/additionalProperties/` - added the new `ask_once` enum value to the request property `experimental/permissions/overrides/additionalProperties/` - the `connected_accounts/additionalProperties/` request property format was generalized from `connectedAccountId` to no format - added the optional property `config/all_connected_accounts` to the response with the `201` status - **2026-05-03** `afeba73724e5`: 13 info - added the new optional request property `experimental/permissions` - added the new optional request property `manage_connections/enable_connection_removal` - added the new optional request property `multi_account` - added the new optional request property `preload` - added the new optional request property `workbench/sandbox_size` - the `manage_connections` request property default value changed from `{"enable":true,"enable_wait_for_connections":false}` to `{"enable":true,"enable_wait_for_connections":false,"enable_connection_removal":true}` - added the non-success response with the status `408` - added the optional property `config/manage_connections/enable_connection_removal` to the response with the `201` status - added the optional property `config/multi_account` to the response with the `201` status - added the optional property `config/workbench/sandbox_size` to the response with the `201` status - added the optional property `warnings` to the response with the `201` status - added the required property `config/preload` to the response with the `201` status - added the required property `config_version` to the response with the `201` status - **2026-03-20** `1a01eea79bb9`: 1 breaking, 9 info - the response property `experimental/assistive_prompt` became optional for the status `201` - the endpoint scheme security `UserApiKeyAuth` was added to the API - added the new optional request property `experimental/custom_toolkits` - added the new optional request property `experimental/custom_tools` - added the new optional request property `workbench/enable` - the `workbench` request property default value changed from `{"enable_proxy_execution":true}` to `{"enable":true,"enable_proxy_execution":true}` - added the optional property `config/workbench/enable` to the response with the `201` status - added the optional property `experimental/custom_toolkits` to the response with the `201` status - added the optional property `experimental/custom_tools` to the response with the `201` status - the `workbench` response's property default value changed from `{"proxy_execution_enabled":true}` to `{"enable":true,"proxy_execution_enabled":true}` for the status `201` - **2026-02-12** `881fa7b9eb11`: 2 breaking, 9 warning, 20 info - removed `subschema #1, subschema #2` from the `toolkits` request property `anyOf` list - the `user_id` request property's minLength was increased from `0` to `1` - removed the request property `connections` - removed the request property `execution` - removed the request property `tools/filters` - removed the request property `tools/overrides` - removed the optional property `config/connections` from the response with the `201` status - removed the optional property `config/execution` from the response with the `201` status - removed the optional property `config/tools/filters` from the response with the `201` status - removed the optional property `config/tools/overrides` from the response with the `201` status - added the new `http` enum value to the `mcp/type` response property for the response status `201` - added the new optional request property `experimental` - added the new optional request property `manage_connections` - added the new optional request property `tags` - added the new optional request property `workbench` - added `subschema #1, subschema #2` to the `toolkits` request property `anyOf` list - added the optional property `config/manage_connections` to the response with the `201` status - added the optional property `config/tags` to the response with the `201` status - added the optional property `config/workbench` to the response with the `201` status - added the optional property `experimental` to the response with the `201` status - removed the `COMPOSIO_GET_TOOL_SCHEMAS` enum value from the `tool_router_tools/items/` response property for the response status `201` - removed the `COMPOSIO_MANAGE_CONNECTIONS` enum value from the `tool_router_tools/items/` response property for the response status `201` - removed the `COMPOSIO_MULTI_EXECUTE_TOOL` enum value from the `tool_router_tools/items/` response property for the response status `201` - removed the `COMPOSIO_REMOTE_BASH_TOOL` enum value from the `tool_router_tools/items/` response property for the response status `201` - removed the `COMPOSIO_REMOTE_WORKBENCH` enum value from the `tool_router_tools/items/` response property for the response status `201` - removed the `COMPOSIO_SEARCH_TOOLS` enum value from the `tool_router_tools/items/` response property for the response status `201` - removed the `HTTP` enum value from the `mcp/type` response property for the response status `201` - added the required property `error/slug` to the response with the `400` status - added the required property `error/slug` to the response with the `401` status - added the required property `error/slug` to the response with the `403` status - added the required property `error/slug` to the response with the `500` status --- [Operation](https://skmtc.dev/composiohq/apis/composio-platform-api/docs/api/v3/tool_router/session/post.md) - [API](https://skmtc.dev/composiohq/apis/composio-platform-api.md) - [Page](https://skmtc.dev/composiohq/apis/composio-platform-api/changes/api/v3/tool_router/session/post)