Properties
| Name | Type | Description |
|---|---|---|
| message_id | string | ID of a ready received message or an accepted sent message in this inbox that has a Message-ID header. |
| text | string | Nonblank reply text; quoted history isn't added. |
| html | string | HTML alternative, sent as supplied. |
| attachments | object | Omitted, null or [] means no attachments. |
| labels | array | Label names, case-sensitive; order and duplicates don't matter. |
| idempotency_key | string | Your unique value for this one operation. Save it with the exact request before sending; repeating that request with the same key within 24 hours returns what the first one did instead of acting again |
JSON Schema
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"$id": "https://artifacts.apis.io/cherami-to/json-schema/cherami-to-reply-input-schema.json",
"title": "ReplyInput",
"x-generated": "2026-11-10",
"x-method": "derived",
"x-generator": "derive-json-schema.py",
"x-source": "openapi/cherami-to-sending-api-openapi.yml#/components/schemas/ReplyInput",
"type": "object",
"properties": {
"message_id": {
"type": "string",
"description": "ID of a ready received message or an accepted sent message in this inbox that has a Message-ID header.",
"pattern": "^[a-f0-9-]{36}$"
},
"text": {
"type": "string",
"description": "Nonblank reply text; quoted history isn't added."
},
"html": {
"type": "string",
"description": "HTML alternative, sent as supplied."
},
"attachments": {
"anyOf": [
{
"type": "array",
"items": {
"$ref": "#/$defs/AttachmentInput"
},
"maxItems": 32
},
{
"type": "null"
}
],
"description": "Omitted, null or [] means no attachments."
},
"labels": {
"type": "array",
"items": {
"$ref": "#/$defs/Label"
},
"maxItems": 32,
"description": "Label names, case-sensitive; order and duplicates don't matter."
},
"idempotency_key": {
"type": "string",
"description": "Your unique value for this one operation. Save it with the exact request before sending; repeating that request with the same key within 24 hours returns what the first one did instead of acting again.",
"pattern": "^[A-Za-z0-9_-]{1,128}$"
}
},
"required": [
"message_id",
"text"
],
"additionalProperties": false,
"$defs": {
"AttachmentInput": {
"type": "object",
"properties": {
"filename": {
"type": "string",
"description": "At most 255 UTF-8 bytes, without control characters, slashes or backslashes.",
"minLength": 1,
"x-max-utf8-bytes": 255
},
"type": {
"type": "string",
"description": "MIME type without parameters.",
"maxLength": 127,
"pattern": "^[A-Za-z0-9!#$&^_.+-]+/[A-Za-z0-9!#$&^_.+-]+$"
},
"content": {
"type": "string",
"description": "The file's bytes as padded base64, without line breaks.",
"contentEncoding": "base64",
"pattern": "^[A-Za-z0-9+/]*={0,2}$"
}
},
"required": [
"filename",
"type",
"content"
],
"additionalProperties": false
},
"Label": {
"type": "string",
"description": "1–128 UTF-8 bytes after trimming, without control characters; case-sensitive.",
"x-max-utf8-bytes": 128
}
}
}
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/cherami-to-reply-input"
All schemas
curl "https://apis.io/api/v1/json-schemas?limit=25"
Calls without X-API-Key need no key. Calls with it need a paid plan — get a key.
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.