Create Session

POST/api/v1/chat

Create a chat session, optionally bound to indexes (locked after the first message).

Query ParametersExpand Collapse

organization_id: optional string

project_id: optional string

Cookie ParametersExpand Collapse

session: optional string

Body ParametersJSONExpand Collapse

index_ids: optional array of string

Indexes this session will retrieve from. Once set and the first message has been sent, the source set is locked for the session’s lifetime. Leave null to create an unbound session.

ReturnsExpand Collapse

last_updated_at: string

ISO-format timestamp showing when the session was last updated.

session_id: string

Unique session identifier.

generated_title: optional string

Auto-generated title derived from the first user message.

index_ids: optional array of string

Indexes this session is bound to. Null on unbound sessions.

job_metadata: optional object { duration_ms, error, export_config_ids, 4 more }

Token usage and status from the most recent run. Null if the session has not been run yet.

duration_ms: optional number

error: optional string

export_config_ids: optional array of string

is_error: optional boolean

total_input_tokens: optional number

total_output_tokens: optional number

turns: optional number

Create Session

curl https://api.cloud.llamaindex.ai/api/v1/chat \
    -X POST \
    -H "Authorization: Bearer $LLAMA_CLOUD_API_KEY"

{
  "last_updated_at": "2026-04-22T12:34:41.342245",
  "session_id": "ses-abc123",
  "generated_title": "What were the main findings in Q3?...",
  "index_ids": [
    "idx-abc123",
    "idx-def456"
  ],
  "job_metadata": {
    "duration_ms": 0,
    "error": "error",
    "export_config_ids": [
      "string"
    ],
    "is_error": true,
    "total_input_tokens": 0,
    "total_output_tokens": 0,
    "turns": 0
  }
}

Returns Examples

{
  "last_updated_at": "2026-04-22T12:34:41.342245",
  "session_id": "ses-abc123",
  "generated_title": "What were the main findings in Q3?...",
  "index_ids": [
    "idx-abc123",
    "idx-def456"
  ],
  "job_metadata": {
    "duration_ms": 0,
    "error": "error",
    "export_config_ids": [
      "string"
    ],
    "is_error": true,
    "total_input_tokens": 0,
    "total_output_tokens": 0,
    "turns": 0
  }
}