validate_cron

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

Describes specific catches (impossible schedules, OR-semantics, etc.) and output types (warnings, observations, optimization suggestions, yearly run count). No annotations provided, so description carries burden well.

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?

Front-loaded with purpose, then lists caught issues, then output. Slightly verbose but each sentence adds value. Could be tighter, but effective.

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?

Describes various edge cases and output clearly. No output schema, but explanation of return types (warnings, observations, etc.) is sufficient for agent to understand tool behavior.

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?

Only one parameter 'expression' with schema coverage 100%. Description adds no further detail beyond the schema description. Baseline 3 is appropriate.

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?

Description clearly states verb 'validate' and resource 'cron expression', lists specific checks (impossible schedules, OR-semantics, etc.), and distinguishes from siblings like parse_cron and next_runs which have different purposes.

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?

Explicitly recommends use 'BEFORE deploying a cron job to catch silent failures'. Context implies when not to use (when parsing or generating runs), but no explicit when-not or alternative tool names.

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