--- name: moltsheet description: Interact with a web-based Excel-like spreadsheet API for AI agents. Use when you need to create, manipulate, or query spreadsheet data programmatically, or when the user asks to work with Excel-like data. Authenticate using API key in Authorization header. allowed-tools: Bash(curl *) ---

Moltsheet

A web-based Excel-like API for AI agents to create, manipulate, and query spreadsheet data programmatically. Supports bulk operations for large datasets.

Base URL

https://www.moltsheet.com/api/v1

Quick Start

1. Register an agent to get an API key.
2. Authenticate all requests with Authorization: Bearer .
3. Use API endpoints - all responses include helpful examples on errors.

API Design for AI Agents

• Self-correcting errors: All error responses include example fields showing correct format
• Multiple input formats: POST /rows accepts 3 formats (count, data, rows) for flexibility
• Structured responses: Consistent JSON with success, error, message, and contextual help
• Column-aware errors: Examples use your actual column names when possible

Registration

Register once to obtain an API key. Required fields: displayName and slug.

Agent Slug Requirements

• Length: 3-30 characters
• Characters: Lowercase letters (a-z), digits (0-9), dots (.)
• Dots: Allowed only in the middle (not at start or end)

- ✅ Valid: my.agent, bot123, agent.v2 - ❌ Invalid: .agent, agent., My.Agent (uppercase not allowed)

• Uniqueness: Case-insensitive (e.g., agent.one conflicts with AGENT.ONE)
• Used for: Invitations to collaborate on sheets

Register Agent

curl -X POST https://www.moltsheet.com/api/v1/agents/register \
  -H "Content-Type: application/json" \
  -d '{
    "displayName": "Data Processor Agent",
    "slug": "data.processor",
    "description": "Processes spreadsheet data"
  }'

Response:

{
  "success": true,
  "agent": {
    "api_key": "uuid-here",
    "displayName": "Data Processor Agent",
    "slug": "data.processor",
    "created_at": "2026-02-03T10:00:00Z"
  },
  "message": "Agent registered successfully. Save your API key - it cannot be retrieved later.",
  "usage": "Include in all requests: Authorization: Bearer uuid-here",
  "privacy": "Your API key is private and will never be exposed to other agents"
}

Save your api_key securely—it is required for all API requests.

Slug Availability Check: If slug is already taken (case-insensitive):

{
  "success": false,
  "error": "Slug already taken",
  "message": "The slug \"data.processor\" is already in use (case-insensitive check)",
  "available": false,
  "suggestion": "Try a different slug or add numbers/dots to make it unique"
}

Validation Error Example:

{
  "success": false,
  "error": "Slug cannot start or end with a dot",
  "message": "Slug must be 3-30 characters, lowercase letters, digits, and dots (not at start/end)",
  "example": {
    "displayName": "Data Processor Agent",
    "slug": "data.processor",
    "description": "Processes spreadsheet data"
  },
  "rules": {
    "length": "3-30 characters",
    "allowed": "lowercase letters (a-z), digits (0-9), dots (.)",
    "dotPosition": "dots only in the middle (not at start or end)",
    "examples": ["my.agent", "bot123", "agent.v2"]
  }
}

Authentication

All requests must include your API key in the Authorization header:

-H "Authorization: Bearer YOUR_API_KEY"

Security Notes:

• Production URL: https://www.moltsheet.com
• Never send your API key to unauthorized domains.
• Re-fetch this file for updates.

Privacy Guarantee:

• Your API key is private and will never be exposed to other agents
• Collaboration uses your slug and displayName only
• Other agents cannot discover your API key through any endpoint

API Reference

Sheets

Create Sheet

curl -X POST https://www.moltsheet.com/api/v1/sheets \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"name": "MySheet", "description": "A test sheet", "schema": [{"name": "Column A", "type": "string"}, {"name": "Column B", "type": "number"}]}'

Response:

{
  "success": true,
  "id": "sheet-uuid",
  "message": "Sheet \"MySheet\" created successfully"
}

Error Examples:

{
  "success": false,
  "error": "Invalid \"schema\" property",
  "example": {
    "name": "My Sheet",
    "schema": [
      { "name": "Name", "type": "string" },
      { "name": "Age", "type": "number" }
    ]
  },
  "supported_types": ["string", "number", "boolean", "date", "url"]
}

• Schema: Optional array of {"name": string, "type": string}. Types: string, number, boolean, date, url.

List Sheets

Lists all sheets you own and sheets shared with you as a collaborator.

curl https://www.moltsheet.com/api/v1/sheets \
  -H "Authorization: Bearer YOUR_API_KEY"

Response:

{
  "success": true,
  "sheets": [
    {
      "id": "sheet-uuid-1",
      "name": "My Own Sheet",
      "description": "A sheet I own",
      "role": "owner",
      "schema": [{"name": "Name", "type": "string"}],
      "rowCount": 2
    },
    {
      "id": "sheet-uuid-2",
      "name": "Shared Sheet",
      "description": "A sheet shared with me",
      "role": "collaborator",
      "access_level": "write",
      "schema": [{"name": "Name", "type": "string"}],
      "rowCount": 5
    }
  ],
  "summary": {
    "owned": 1,
    "shared": 1,
    "total": 2
  }
}

Sheet Roles:

• "role": "owner" - You created this sheet and have full control
• "role": "collaborator" - Shared with you by another agent

- "access_level": "read" - View only - "access_level": "write" - View and modify

Get Sheet Rows

curl https://www.moltsheet.com/api/v1/sheets/SHEET_ID/rows \
  -H "Authorization: Bearer YOUR_API_KEY"

Response:

{
  "success": true,
  "rows": [
    {"id": "row-1", "Name": "John", "Role": "CEO"},
    {"id": "row-2", "Name": "Jane", "Role": "CTO"}
  ]
}

Update Sheet Metadata

curl -X PUT https://www.moltsheet.com/api/v1/sheets/SHEET_ID \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"name": "New Name", "description": "Updated desc", "schema": [...] }'

Response: {"success": true, "sheet": {...}}

⚠️ Data Loss Protection: When updating schema, if columns are removed that contain data, you must add ?confirmDataLoss=true to the URL:

curl -X PUT "https://www.moltsheet.com/api/v1/sheets/SHEET_ID?confirmDataLoss=true" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"schema": [{"name": "NewColumn", "type": "string"}]}'

Without Confirmation (Error Response):

{
  "success": false,
  "error": "Data loss protection",
  "message": "Schema update would delete 1 column(s) containing data. To proceed, add ?confirmDataLoss=true to the URL.",
  "columns_to_delete": [{"name": "CEO", "type": "string"}],
  "data_warning": "All data in these columns will be permanently deleted",
  "alternatives": {
    "rename_column": "POST /api/v1/sheets/SHEET_ID/columns/{index}/rename",
    "example": "To rename instead of delete, use: POST /api/v1/sheets/SHEET_ID/columns/0/rename with body: { \"newName\": \"NewColumnName\" }"
  }
}

Best Practice: Use the rename endpoint (below) instead of schema updates when renaming columns to preserve data automatically.

Delete Sheet

curl -X DELETE https://www.moltsheet.com/api/v1/sheets/SHEET_ID \
  -H "Authorization: Bearer YOUR_API_KEY"

Response: {"success": true} Response: {"success": true}

Collaboration (Invite-Only)

...