Custom Claude Code skill fixes Monday.com description bug
David Shimon built a custom `/create-monday-task` skill for Claude Code after discovering that the Monday.com MCP server lacked a tool for setting item descriptions, causing AI-created tasks to land content in the comments thread instead of the description field.
Score breakdown
Encode agent failure modes as reusable skills and guardrails — rather than manual corrections — so the fix benefits the whole team and survives future model or tool updates.
- 01Claude Code was placing Monday.com task descriptions in the updates thread (comments) instead of the description field due to a missing MCP tool.
- 02The MCP server exposes `create_update`, which creates a comment-style entry — not a description — despite its misleading name.
- 03Grepping a 51KB Monday GraphQL schema via `all_monday_api` revealed the `set_item_description_content` mutation.
David Shimon describes a frustrating but instructive debugging session: Claude Code was creating Monday.com tasks with empty description fields, placing the intended content in the updates thread instead. The root cause was a naming ambiguity in the MCP server — `create_update` sounds like it updates an item, but it actually creates a comment-style entry. More critically, no MCP tool existed for setting item descriptions at all, making the correct path completely invisible to any agent scanning the available tool list.
The mutation exists in the API (added January 26, 2026) but the MCP server hasn't been updated to expose it as a dedicated tool, so raw GraphQL is the only path to reach it.
The investigation involved having Claude read an existing task to identify that descriptions are stored as `item_description`, then dumping the full Monday GraphQL schema via the `all_monday_api` escape hatch and filtering for mutations containing "description." This surfaced `set_item_description_content`, which sets an item description as markdown. The mutation exists in the API (added January 26, 2026) but the MCP server hasn't been updated to expose it as a dedicated tool, so raw GraphQL is the only path to reach it.
The fix is a `/create-monday-task` skill for Claude Code that enforces the correct two-call sequence — `create_item` first, then `set_item_description_content` via `all_monday_api` — and includes a hard "NEVER use `create_update`" guardrail with an explanation of why. Shimon filed a GitHub issue (`mondaycom/mcp/issues/314`) requesting that `create_item` simply accept a description parameter natively. The broader lesson he draws: manual corrections help once, but encoding the fix as a shared skill helps an entire team indefinitely, and the investigation itself builds a clearer mental model of how agents select and use tools.
Key facts
- 01Claude Code was placing Monday.com task descriptions in the updates thread (comments) instead of the description field due to a missing MCP tool.
- 02The MCP server exposes `create_update`, which creates a comment-style entry — not a description — despite its misleading name.
- 03Grepping a 51KB Monday GraphQL schema via `all_monday_api` revealed the `set_item_description_content` mutation.
- 04`set_item_description_content` was added to the Monday API on January 26, 2026 but has not yet been added to the MCP server.
- 05The correct flow requires two API calls: `create_item` first, then `set_item_description_content` via raw GraphQL.