Google Search

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

Despite annotations marking readOnlyHint, the description goes far beyond by disclosing caching behavior (24h TTL), timing expectations (~4s first call, ~2s subsequent), CAPTCHA fallback with human interaction, and the fail-fast env var. This provides valuable operational context that annotations alone do not convey.

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 somewhat long but front-loaded with the core purpose. Each sentence contributes unique operational facts (performance, caching, CAPTCHA, env vars) without redundancy. The 'Default limit 10 (max 20)' slightly duplicates schema, but overall it 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?

The description covers all key operational aspects: output structure, caching, performance, error handling (CAPTCHA), and configuration via env vars. With an output schema present, return values are already defined, and the description fills the remaining gaps comprehensively.

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?

The input schema fully documents both parameters ('query' and 'limit') with descriptions and constraints, so the description adds little param-specific detail beyond the default limit and max. The caching and env var info are not directly about parameter syntax, so 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?

The description clearly states 'Single Google search -> title/url/snippet per result', specifying the exact resource (Google search) and output. The word 'single' differentiates it from sibling search_parallel, and the context makes it unambiguous what this tool performs.

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 gives clear practical usage guidance: 'prefer re-querying over caching results yourself', how to bypass cache for fresh queries, and the CAPTCHA/cloud-mode behavior. It implies the single-query use case but doesn't explicitly contrast with alternatives like search_parallel, so no explicit exclusion.

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