compare_pricing

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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so safety is covered without description help. The description adds that the result is a structured before/after diff (prices, plans, additions/removals), which is useful, but does not discuss the archived-snapshot fallback beyond what the schema already states.

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?

A single sentence, front-loaded with the core action and followed by the concrete return content. Zero filler; every clause earns its place.

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 an output schema present and 100% param coverage, the definition supplies everything needed to invoke the tool correctly and even previews the comparison result. The only shortfall is the absence of guidance on how it relates to sibling comparison/list tools.

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%, so date formats, the 'latest' keyword, the default date_b and the url example are all documented in the schema. The description adds no parameter-level syntax or constraints beyond that, so the baseline 3 applies.

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?

States a specific verb (Compare) and resource (one pricing page at two dates) and enumerates the outputs: prices and plans on each date plus additions/removals. An agent can distinguish this from pricing_at or pricing_timeline, which target a single point or series rather than a two-date diff.

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 two-date framing implies when to reach for it, but there is no explicit when-not guidance and no sibling is named as an alternative. An agent must infer the selection criteria from context rather than reading it in the description.

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