search_history_stats

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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the operation's safety profile is covered. The description adds one genuinely new behavioral fact (local-only, no API quota consumption), which is valuable, but says nothing about result format or size bounds beyond the categories listed.

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?

Two tight clauses with zero filler, and the core purpose is front-loaded ahead of the quota note. Slightly clipped to the point of leaving the 'sidecar' concept unexplained.

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?

For a simple read-only stats tool with full schema coverage and no output schema, the description is adequate but thin: it never explains what the 'sidecar' is or how recency is defined, so an agent lacks full grounding on the returned data.

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 both parameters (top_n, response_format) are fully documented with defaults and enum semantics in the schema. The description adds no parameter-level detail, so 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 ('analytics over') and resource ('the local search-history sidecar'), then enumerates the three outputs it produces: top queries, type breakdown, recency. This clearly separates it from the search siblings like history_search, though it never names that alternative directly.

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?

No when-to-use or when-not-to-use guidance is given. The 'Quota: local only (no API)' note is useful context but does not tell the agent when to pick this over history_search or following_analytics.

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