search_console_analytics_compare_periods

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

With no annotations provided, the description carries the full burden and does excellently: it discloses the tool is read-only, issues two REST calls per invocation, does not diff/merge periods, requires agent alignment by first key, and documents return shape. This far exceeds basic safety disclosure.

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?

Every sentence earns its place: purpose, return shape, critical caveat about no merging, safety/read-only, call count, defaults, and alternative tool. The description is front-loaded with the core function and remains dense without fluff.

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?

The tool has no output schema, so the description compensates by specifying the exact return object shape and per-row fields. It also explains alignment logic, default behavior, and gives an explicit sibling alternative, making the tool self-contained for correct invocation.

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% with detailed parameter descriptions, so baseline is 3. The description adds value by explaining the return structure (keys, clicks, impressions, ctr, position), the alignment requirement, and defaults like dimensions=['query'] and row_limit=100, which reinforces but goes slightly beyond 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 opens with a specific verb and resource: 'Query Search Console search analytics twice and return both periods side-by-side.' It clearly distinguishes this tool from the single-period sibling by contrasting return shape and explicitly naming the alternative for single-period queries.

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?

It explicitly states when to use this tool versus alternatives: 'For a single-period query use search_console_analytics_query.' It also clarifies that the tool does not diff/merge and the agent must align rows, setting clear expectations for how to use the returned data.

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