Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already indicate readOnlyHint=false and destructiveHint=false, clarifying it's a mutation but not destructive. The description adds valuable context beyond that: it specifies the returned payload (normalized schedule and next_run_at), explains the 'manual' schedule type runs only on demand, and mentions the 'activate' flag for draft mode. It doesn't address concurrency or failure behavior, but the added detail is substantial.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single focused paragraph that starts with the action, then efficiently enumerates all schedule types with their required fields, and closes with the return value. There is no redundancy or filler; every sentence adds information needed to call the tool correctly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (nested schedule object with seven types) and no output schema, the description is thorough. It covers all schedule types, return values, and the activation flag. Missing are error conditions and how to obtain agent_id, but those are apparent from the schema and sibling tools (create_agent). Overall, it provides enough context for a competent agent to invoke the tool correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so all parameters are documented in the schema. The description adds significant meaning by detailing each schedule type (once, interval, hourly, daily, weekly, cron, manual) with specific constraints like interval_minutes 5-1440, days_of_week 0=Sunday..6, and timezone handling. This goes well beyond the schema's generic 'Schedule object' description, enhancing the agent's ability to construct valid inputs.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool creates a scheduled task for an agent, enumerates all supported schedule types with specific constraints, and explains the return value. It's distinct from siblings like list_agent_tasks by focusing on creation, and the detailed schedule types leave no ambiguity about what the tool does.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explains what the tool does and covers various schedule scenarios, but it does not explicitly mention when to use this over alternatives (e.g., list_agent_tasks for viewing, or update_agent_task if it existed). It implies usage for creating schedules but gives no clear guidance on when not to use it or how it relates to other task-management tools.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.