Tools

The Sim API has more than 200 operations. Instead of one tool per operation, which would crowd your app's tool list and your agent's context, the server exposes four tools. The agent searches for an operation, reads its inputs, and calls it.

ToolDoes
search_operationsFinds operations by keyword ("table rows") or by area (tables, workflows, knowledge, …). Returns each operation's name, method, path, summary, and the tool that runs it.
describe_operationReturns an operation's description and the JSON Schema of its path parameters, query, body, and headers.
call_read_operationRuns an operation that only needs read access, such as listWorkspaces, queryRows, or getWorkflowRun.
call_write_operationRuns an operation that needs write access: one that creates, changes, runs, or deletes something, or reaches out to another service, such as createTable, executeWorkflow, or listMcpServerTools.

Reads and writes are separate tools so your app can approve reads once and still ask you before each change.

Calling an operation

Operation names match the CLI and the API reference. A call names the operation and fills the parts of the request it needs:

{
  "operation": "listTableRows",
  "params": { "tableId": "tbl_8f2c" },
  "query": { "workspaceId": "ws_91ab", "limit": 50 }
}
FieldHolds
paramsPath parameters, such as tableId or workflowId
queryQuery-string parameters; most operations need workspaceId
bodyThe JSON request body (write operations only)
headersHeaders the operation declares, such as upload-token

The result is the same JSON the API returns, usually { "data": … }. List operations page with limit and cursor. A failed call returns the API's error, such as { "error": { "code": "NOT_FOUND", "message": "…" } }, so the agent can correct its request.

Limits

  • Same rules as the API. Permissions, rate limits, and request validation are the API's own; nothing is looser through MCP.
  • 1 MiB per result. Page through larger lists with limit and cursor.
  • No streaming. Run a workflow without stream: true to wait for its result, or with async: true and poll getWorkflowRun.
  • No file bytes. Downloads, knowledge base exports, and multipart document uploads are not available over MCP; use the CLI or the API.
Authentication