Properties
| Name | Type | Description |
|---|---|---|
| id | string | |
| role | string | |
| parts | array | The message parts, in order |
| sequence | integer | The paging key |
| status | string | `pending` is the placeholder a running turn fills in (the row GET …/generation names as messageId); `complete` is a settled reply — a reply the output cap cut short included, so read `finishReason` fo |
| finishReason | string | Why the turn stopped, on a settled assistant message, in one vocabulary over every provider: `stop` (a natural end), `length` (the `maxOutputTokens` cap or the model’s own ceiling cut a round of this |
| model | string | |
| providerSlug | string | |
| blockedReason | string | |
| error | string | Why a failed turn produced no reply |
| errorCode | string | Stable chat error classification when available. `credit_exhausted` and `model_not_entitled` mean the provider account, not the request; neither is `rate_limited`. `budget_exceeded` means a budget cap |
| usage | object | The token counters the finished turn recorded and the catalog cost estimate stamped beside them; absent until the turn settles. A failed turn carries what it consumed — its finished model rounds and, |
| createdAt | integer | Epoch ms — when the row was created (for an assistant row, when its turn started) |
JSON Schema
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"$id": "https://raw.githubusercontent.com/api-evangelist/tale-dev/main/json-schema/tale-dev-message-schema.json",
"title": "Message",
"x-generated": "2026-10-09",
"x-method": "derived",
"x-generator": "derive-json-schema.py",
"x-source": "openapi/tale-dev-openapi.yml#/components/schemas/Message",
"type": "object",
"required": [
"id",
"role",
"parts",
"sequence",
"status",
"createdAt"
],
"properties": {
"id": {
"type": "string"
},
"role": {
"type": "string",
"enum": [
"user",
"assistant"
]
},
"parts": {
"type": "array",
"items": {
"$ref": "#/$defs/MessagePart"
},
"description": "The message parts, in order"
},
"sequence": {
"type": "integer",
"description": "The paging key"
},
"status": {
"type": "string",
"enum": [
"pending",
"complete",
"failed",
"cancelled"
],
"description": "`pending` is the placeholder a running turn fills in (the row GET …/generation names as messageId); `complete` is a settled reply — a reply the output cap cut short included, so read `finishReason` for that; `cancelled` is a turn stopped through DELETE …/generation — `parts` and `usage` hold what had streamed; `failed` carries `error`, and `usage` when the turn had consumed any."
},
"finishReason": {
"type": "string",
"enum": [
"stop",
"length",
"tool-calls",
"content-filter",
"cancelled",
"other"
],
"description": "Why the turn stopped, on a settled assistant message, in one vocabulary over every provider: `stop` (a natural end), `length` (the `maxOutputTokens` cap or the model’s own ceiling cut a round of this reply short — the final text, or, in a tool-calling turn, the tool calls of an earlier round: every call of that round is withheld, its tool-result reads `status: \"invalid_args\"` — the message saying whether its arguments were cut or complete — and the final text may be whole; the status still reads `complete`), `tool-calls` (the final round ended on tool calls), `content-filter` (the provider’s or the platform’s filter), `cancelled` (stopped through DELETE …/generation), `other` (a reason the provider named that has no bucket here). Absent when the provider reported none."
},
"model": {
"type": "string"
},
"providerSlug": {
"type": "string"
},
"blockedReason": {
"type": "string"
},
"error": {
"type": "string",
"description": "Why a failed turn produced no reply"
},
"errorCode": {
"type": "string",
"enum": [
"missing_api_key",
"credit_exhausted",
"model_not_entitled",
"auth_error",
"model_not_found",
"unsupported_parameter",
"output_cap_too_high",
"token_limit",
"rate_limited",
"content_filter",
"context_length",
"tool_failure",
"provider_unreachable",
"provider_error",
"thread_busy",
"budget_exceeded",
"generic"
],
"description": "Stable chat error classification when available. `credit_exhausted` and `model_not_entitled` mean the provider account, not the request; neither is `rate_limited`. `budget_exceeded` means a budget cap that binds the key holder was reached after the send was accepted, so the turn never ran; a send made once a cap is reached is refused up front with 429 `BUDGET_EXCEEDED`."
},
"usage": {
"type": "object",
"additionalProperties": false,
"description": "The token counters the finished turn recorded and the catalog cost estimate stamped beside them; absent until the turn settles. A failed turn carries what it consumed — its finished model rounds and, if the provider had already accepted the request, the round that failed; a round the provider refused (an HTTP error status, or a refusal such as a rate limit reported before any answer or positive reported usage) adds nothing, so a turn refused on its first round carries none. Counts are the provider’s own unless `estimated` is present.",
"properties": {
"inputTokens": {
"type": "integer",
"description": "Prompt tokens — the assistant’s instructions and tool schemas included"
},
"outputTokens": {
"type": "integer",
"description": "Reply tokens, the reasoning share included"
},
"cachedInputTokens": {
"type": "integer",
"description": "The share of `inputTokens` the provider served from its prompt cache"
},
"reasoningTokens": {
"type": "integer",
"description": "The share of `outputTokens` spent thinking before the reply — absent when the provider reported no count (a `0` is a reported zero)"
},
"costEstimateCents": {
"type": "number",
"minimum": 0,
"description": "The turn’s cost in US cents (fractional) from the catalog price the organization ledger also books — the same figure as the ledger; absent when the catalog publishes no price for the model. Cached input is priced at the input rate, so on a cached turn the figure is an upper bound; estimated when the provider’s count was lost (`estimated`)."
},
"estimated": {
"type": "boolean",
"enum": [
true
],
"description": "Present when the counts are the platform’s own estimate — the provider’s usage frame was lost (a cancelled turn, or one that failed mid-stream, typically) or never sent — so the cost is an estimate too"
},
"stepLimitHit": {
"type": "boolean",
"enum": [
true
],
"description": "Present when the tool loop spent its whole round budget and the final round had tools withheld — the answer may have been forced"
}
}
},
"createdAt": {
"type": "integer",
"minimum": 0,
"description": "Epoch ms — when the row was created (for an assistant row, when its turn started)"
}
},
"$defs": {
"ApprovalPart": {
"type": "object",
"required": [
"type",
"approvalId",
"question"
],
"properties": {
"type": {
"type": "string",
"enum": [
"approval"
]
},
"approvalId": {
"type": "string"
},
"question": {
"type": "string"
},
"decision": {
"type": "string",
"enum": [
"approved",
"rejected"
]
}
}
},
"AttachmentPart": {
"type": "object",
"required": [
"type",
"name",
"mediaType"
],
"properties": {
"type": {
"type": "string",
"enum": [
"attachment"
]
},
"name": {
"type": "string"
},
"mediaType": {
"type": "string"
},
"fileId": {
"type": "string"
},
"sizeBytes": {
"type": "integer"
},
"url": {
"type": "string"
},
"text": {
"type": "string",
"description": "Extracted text, when any"
}
}
},
"MessagePart": {
"description": "One ordered piece of a message, discriminated by `type`: the `mapping` names the schema each kind validates against (`TextPart` … `ApprovalPart`), so a discriminator-honouring validator resolves every part. The kinds listed are the vocabulary as of this version; the set is additive, so a client renders a kind it does not know as opaque.",
"oneOf": [
{
"$ref": "#/$defs/TextPart"
},
{
"$ref": "#/$defs/ReasoningPart"
},
{
"$ref": "#/$defs/AttachmentPart"
},
{
"$ref": "#/$defs/ToolCallPart"
},
{
"$ref": "#/$defs/ToolResultPart"
},
{
"$ref": "#/$defs/ApprovalPart"
}
]
},
"ReasoningPart": {
"type": "object",
"required": [
"type",
"text"
],
"description": "The model’s reasoning ahead of its reply — display-only, never replayed to the model; it may quote the assistant’s own instructions verbatim, so it is not safe to render as the answer.",
"properties": {
"type": {
"type": "string",
"enum": [
"reasoning"
]
},
"text": {
"type": "string"
}
}
},
"TextPart": {
"type": "object",
"required": [
"type",
"text"
],
"properties": {
"type": {
"type": "string",
"enum": [
"text"
]
},
"text": {
"type": "string"
}
}
},
"ToolCallPart": {
"type": "object",
"required": [
"type",
"callId",
"capabilityId",
"input"
],
"properties": {
"type": {
"type": "string",
"enum": [
"tool-call"
]
},
"callId": {
"type": "string"
},
"capabilityId": {
"type": "string"
},
"input": {}
}
},
"ToolResultPart": {
"type": "object",
"required": [
"type",
"callId",
"capabilityId",
"output",
"structured"
],
"properties": {
"type": {
"type": "string",
"enum": [
"tool-result"
]
},
"callId": {
"type": "string"
},
"capabilityId": {
"type": "string"
},
"output": {},
"structured": {
"type": "boolean",
"description": "False when the capability declares no output schema"
}
}
}
}
}
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