Microsoft Excel (Microsoft Graph workbook API) vs Smartsheet API + MCP

Microsoft Excel (Microsoft Graph workbook API)

Ranges, tables, charts and 366 worksheet function endpoints are reachable over REST with a public OpenAPI, and a non-persistent session lets an agent test changes without saving them. The reference pages list delegated permissions only, with Files.ReadWrite as the least privileged scope, and writes take no idempotency key.

Smartsheet API + MCP

The REST API has a public OpenAPI 3.0.3 spec with 187 operations, Markdown docs and llms.txt, and the hosted MCP server loads its 83 documented tools by toolset. API access needs a Business plan or higher, and the status page lists eight incidents marked major or critical between 15 July and 21 September 2026.

Microsoft Excel (Microsoft Graph workbook API)

1. Create a session with POST /workbook/createSession and send workbook-session-id on every call. Persistent sessions expire after about 5 minutes idle
2. Set persistChanges to false when you only need a calculation or a chart image, so nothing is saved to the file
3. Send one request at a time per workbook and wait for each response. Microsoft warns that parallel writes cause throttling, timeouts and merge conflicts
4. Add rows in one call with a two-dimensional values array, and check the table before repeating a row add that returned 504
5. Read bounded addresses such as A1:D500. A whole-column range such as C:C returns null for values, and writes to it are refused

Smartsheet API + MCP

1. Send writes to one sheet one at a time. Parallel updates with the same token return error 4004
2. Batch row changes, up to 500 rows a call, and add allowPartialSuccess=true to get per-row failures instead of a failed batch
3. On error 4003 (HTTP 429) wait at least 60 seconds before retrying. The limit is 300 requests a minute per token, 30 for attachments and cell history
4. Through MCP, call get_columns before filtering or writing. Column names are case-sensitive and guesses fail validation
5. Use the regional host that matches the account (api.smartsheet.com, .eu or .au). Tokens don't work across regions