Properties
| Name | Type | Description |
|---|---|---|
| model | string | Required. ultramarine-1-flash |
| max_tokens | integer | Required. Positive integer, including reasoning |
| messages | array | Required. user and assistant turns, ending with a user turn |
| system | string | String or text blocks |
| output_config | object | Object with effort and format fields |
| thinking | object | {"type": "adaptive"}, optionally with "display": "omitted" |
| stream | boolean | true or false |
| tools | array | Custom tools with name, description, input_schema, and optional strict |
| tool_choice | string | auto, any, none, or tool object |
| temperature | number | Number, 0–1 |
| top_p | number | Number, 0–1 |
| top_k | integer | Integer, -1 or greater |
| metadata | object | Object with user_id field |
| cache_control | object | {"type": "ephemeral"} |
| context_management | object | Object with edits array |
JSON Schema
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"$id": "https://artifacts.apis.io/paper-instruments/json-schema/paper-instruments-post-v1-messages-request-schema.json",
"title": "PostV1MessagesRequest",
"x-generated": "2026-10-29",
"x-method": "derived",
"x-generator": "derive-json-schema.py",
"x-source": "openapi/_ae-authored/paper-instruments-openapi-generated.yml#/components/schemas/PostV1MessagesRequest",
"type": "object",
"properties": {
"model": {
"type": "string",
"description": "Required. ultramarine-1-flash"
},
"max_tokens": {
"type": "integer",
"description": "Required. Positive integer, including reasoning"
},
"messages": {
"type": "array",
"description": "Required. user and assistant turns, ending with a user turn"
},
"system": {
"type": "string",
"description": "String or text blocks"
},
"output_config": {
"type": "object",
"description": "Object with effort and format fields"
},
"thinking": {
"type": "object",
"description": "{\"type\": \"adaptive\"}, optionally with \"display\": \"omitted\""
},
"stream": {
"type": "boolean",
"description": "true or false"
},
"tools": {
"type": "array",
"description": "Custom tools with name, description, input_schema, and optional strict"
},
"tool_choice": {
"type": "string",
"description": "auto, any, none, or tool object"
},
"temperature": {
"type": "number",
"description": "Number, 0–1"
},
"top_p": {
"type": "number",
"description": "Number, 0–1"
},
"top_k": {
"type": "integer",
"description": "Integer, -1 or greater"
},
"metadata": {
"type": "object",
"description": "Object with user_id field"
},
"cache_control": {
"type": "object",
"description": "{\"type\": \"ephemeral\"}"
},
"context_management": {
"type": "object",
"description": "Object with edits array"
}
},
"required": [
"model",
"max_tokens",
"messages"
]
}
Work with this as data
Every JSON Schema here is available over the APIs.io API and to AI agents over MCP.
MCP server
One button, every client — Claude, Cursor, VS Code and the rest.
https://apis.io/mcp
Tools for schemas
4 MCP tools reach this
find_json_schemasBrowse and filter every JSON Schema in the catalog.apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.resolveTurn a domain, URL or GitHub org into the provider it belongs to.find_cohortsEvery scored population of providers in the catalog.
Call it yourself
curl for this page
This JSON Schema
curl "https://apis.io/api/v1/json-schemas/paper-instruments-post-v1-messages-request"
All schemas
curl "https://apis.io/api/v1/json-schemas?limit=25"
Discovery needs no key. Ratings and market analysis are Pro.
Get an API key
Free tier, no form to fill in. Signing in shares your email address with us — we store it to create your key and to recognise you if you sign in with another provider. See our Privacy Policy and Terms.
A second provider on the same verified email joins the account you already have.