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

With no annotations, the description carries the full burden of behavioral disclosure. It discloses that it uses cron-parser for real calculations (not model guesses), interprets fields in UTC for deterministic results, and costs $0.02 USDC per call. These are meaningful behavioral details, though error handling and edge cases are not covered.

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 three sentences, front-loaded with the core function, then adds parser details, UTC handling, and cost. Every sentence provides distinct value with no redundancy or fluff, making it highly concise and well-structured.

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 an output schema exists, the description does not need to explain return values. It covers the tool's purpose, calculation method, timezone behavior, and cost, which is quite complete for a simple computation tool. However, it lacks explicit usage guidelines and error behavior, preventing a perfect score.

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 the baseline is 3. The description adds context about UTC interpretation and cron-parser usage, which indirectly informs how parameters like cron_expression and from_date behave, but it does not add explicit parameter-level semantics beyond the schema.

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 calculates the next real executions of a cron expression using cron-parser, which is a specific verb+resource. It distinguishes itself from sibling tools (validar_regex, validar_sql) by focusing on cron expressions and their execution timing, not just regex or SQL validation.

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 implies usage by explaining it computes next executions and uses a real parser, but it does not explicitly state when to use this tool vs alternatives or provide exclusions. The UTC timezone note and cost hint at appropriate contexts, but no direct comparison to siblings is given, so guidance is only implied.

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