parse_cron

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

Annotations provide readOnlyHint, and the description adds behavioral context beyond that: it produces a human-readable description and next run times, and supports both standard cron fields and special strings. It does not discuss error behavior, but the read-only nature is already covered by annotations.

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 sentence, front-loaded with the core action and resource. Every phrase adds useful information, with no filler or redundant restatement of the tool name.

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?

With no output schema, the description adequately communicates what the tool returns: a human-readable description and next run times. Combined with the self-documenting parameters for timezone and count, this is sufficient for an agent to call the tool correctly, though a bit more detail about output format would make it fully complete.

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 description coverage is 100%, and each parameter already has a clear description with examples. The tool description adds no extra parameter semantics beyond mentioning special strings, which the schema also implies. The baseline of 3 applies because the schema does the heavy lifting.

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 states a specific verb ('Parse'), a specific resource ('a cron expression'), and the expected outputs ('human-readable description' and 'next run times'). It clearly distinguishes the tool from unrelated siblings like parse_user_agent and decode_jwt.

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 makes the intended use clear: parse cron expressions and calculate future runs. It also scopes input to standard 5-field cron and special strings. It does not mention alternatives, but no direct alternative exists among the siblings, so the context is clear enough.

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