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Letta Groups API

Coordinate multi-agent groups (supervisor/worker, round-robin, sleep-time).

Letta Groups API is one of 41 APIs that Letta publishes on the APIs.io network, described by a machine-readable OpenAPI specification.

This API exposes 14 JSON Schema definitions.

Tagged areas include Group. The published artifact set on APIs.io includes an OpenAPI specification, API documentation, pricing, a changelog, and 14 JSON Schemas.

This API exposes 11 operations across 8 paths, and defines 46 schemas. It is described by OpenAPI 3.1.0, at version 1.0.0.

Requests are made against 3 base URLs: https://api.letta.com, https://app.letta.com, http://localhost:8283.

11 operations 8 paths 46 schemas 1 DELETE4 GET5 PATCH1 POST

Metadata

The identity and technical contract details declared by the specification.

Specification
OpenAPI 3.1.0
API Version
1.0.0
Base URL
https://api.letta.com
Authentication
HTTP Bearer
Contact
License
Resource Areas
1

Authentication & Security 1

Letta Groups API declares 1 security scheme for authenticating requests. It accepts HTTP bearer tokens (bearerAuth). By default, every request must be authenticated.

Paths & Operations 11

Across 8 paths, the API surfaces 11 operations — 1 DELETE, 4 GET, 5 PATCH, 1 POST. Each is listed below with its method, path, parameters, and response codes.

Groups 11

Coordinate multi-agent groups (supervisor/worker, round-robin, sleep-time).

GET
/v1/groups/deprecated
List Groups
list_groups 7 params → 200422
POST
/v1/groups/deprecated
Create Group
create_group 1 param body → 200422
GET
/v1/groups/countdeprecated
Count Groups
count_groups → 200422
GET
/v1/groups/{group_id}deprecated
Retrieve Group
retrieve_group 1 param → 200422
PATCH
/v1/groups/{group_id}deprecated
Modify Group
modify_group 2 params body → 200422
DELETE
/v1/groups/{group_id}deprecated
Delete Group
delete_group 1 param → 200422
PATCH
/v1/groups/{group_id}/messages/{message_id}deprecated
Modify Group Message
modify_group_message 2 params body → 200422
GET
/v1/groups/{group_id}/messagesdeprecated
List Group Messages
list_group_messages 10 params → 200422
PATCH
/v1/groups/{group_id}/reset-messagesdeprecated
Reset Group Messages
reset_group_messages 1 param → 200422
PATCH
/v1/groups/{group_id}/blocks/attach/{block_id}deprecated
Attach Block to Group
attach_block_to_group 2 params → 200422
PATCH
/v1/groups/{group_id}/blocks/detach/{block_id}deprecated
Detach Block from Group
detach_block_from_group 2 params → 200422

Schemas 46

The contract defines 46 schemas that model the data the API accepts and returns. The most detailed are Group (18 properties), ToolReturnMessage (16 properties), ApprovalResponseMessage (14 properties), ReasoningMessage (13 properties). Each schema is shown below with its type and property counts.

SleeptimeManagerUpdate
object
3 properties
UpdateSystemMessage
object
2 properties 1 required
ApprovalReturn
object
4 properties 2 required
SystemMessage
object
A message generated by the system. Never streamed back on a response, only used for cursor pagination. Args: id (str): The ID of the message date (datetime): T…
11 properties 3 required
CompactionStats
object
Statistics about a memory compaction operation.
6 properties 4 required
UpdateReasoningMessage
object
2 properties 1 required
EventMessage
object
A message for notifying the developer that an event that has occured (e.g. a compaction). Events are NOT part of the context window.
12 properties 4 required
ImageContent
object
2 properties 1 required
UserMessage
object
A message sent by the user. Never streamed back on a response, only used for cursor pagination. Args: id (str): The ID of the message date (datetime): The date…
11 properties 3 required
AssistantMessage
object
A message sent by the LLM in response to user input. Used in the LLM context. Args: id (str): The ID of the message date (datetime): The date the message was c…
11 properties 3 required
ToolCallDelta
object
3 properties
UpdateAssistantMessage
object
2 properties 1 required
HiddenReasoningMessage
object
Representation of an agent's internal reasoning where reasoning content has been hidden from the response. Args: id (str): The ID of the message date (datetime…
12 properties 3 required
letta__schemas__letta_message__ToolReturn
object
6 properties 3 required
LettaUserMessageContentUnion
TextContent
object
3 properties 1 required
SleeptimeManager
object
3 properties 1 required
HTTPValidationError
object
1 property
RoundRobinManager
object
2 properties
ToolReturnMessage
object
A message representing the return value of a tool call (generated by Letta executing the requested tool). Args: id (str): The ID of the message date (datetime)…
16 properties 5 required
ManagerType
string
ApprovalResponseMessage
object
A message representing a response form the user indicating whether a tool has been approved to run. Args: id (str): The ID of the message date (datetime): The…
14 properties 2 required
LettaToolReturnContentUnion
MessageType
string
ReasoningMessage
object
Representation of an agent's internal reasoning. Args: id (str): The ID of the message date (datetime): The date the message was created in ISO format name (Op…
13 properties 3 required
GroupCreate
object
6 properties 2 required
Base64Image
object
4 properties 2 required
Group
object
18 properties 4 required
SummaryMessage
object
A message representing a summary of the conversation. Sent to the LLM as a user or system message depending on the provider.
12 properties 3 required
ValidationError
object
3 properties 3 required
DynamicManagerUpdate
object
4 properties
UpdateUserMessage
object
2 properties 1 required
ApprovalRequestMessage
object
A message representing a request for approval to call a tool (generated by the LLM to trigger tool execution). Args: id (str): The ID of the message date (date…
12 properties 3 required
SupervisorManagerUpdate
object
2 properties 1 required
LettaImage
object
5 properties 1 required
GroupUpdate
object
5 properties
VoiceSleeptimeManagerUpdate
object
4 properties
UrlImage
object
2 properties 1 required
LettaMessageUnion
LettaAssistantMessageContentUnion
VoiceSleeptimeManager
object
4 properties 1 required
RoundRobinManagerUpdate
object
2 properties
ToolCall
object
3 properties 3 required
DynamicManager
object
4 properties 1 required
SupervisorManager
object
2 properties 1 required
ToolCallMessage
object
A message representing a request to call a tool (generated by the LLM to trigger tool execution). Args: id (str): The ID of the message date (datetime): The da…
12 properties 3 required

Specification

The full machine-readable OpenAPI contract behind this narrative.

Source

letta-groups-api-openapi.yml Raw ↑

Other APIs Letta publishes across the network.

Letta Code
Letta Admin API
Letta Agents API
Letta Archives API
Letta Blocks API
Letta Chat API
Letta Client-Side Access Tokens API
Letta Conversations API
Letta Device Storage API
Letta Embeddings API
Letta Environments API
Letta Feeds API
Where this information came from

This is an independent, third-party profile of Letta Groups API, published by API Evangelist. We do not operate, host, resell, or support these APIs, and we are not affiliated with or endorsed by the company unless stated above. Everything here is built from publicly available information — the company's own site, developer portal, documentation, public repositories, and the specifications it publishes for public use. Nothing is obtained by breaching a system, defeating an access control, or using credentials.

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