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

Annotations already cover safety (readOnly, idempotent, non-destructive), so the description correctly focuses on output shape: recurring-principle candidates, tensions, counterpoints, actionable advice, follow-up questions, URLs, coverage and limitations. The 16-source cap is useful operational context. It doesn't explain pagination or how coverage/limitations are derived, keeping it short of a 5.

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?

Front-loaded with purpose in the first clause, then return contents and usage priority in a compact block. Slightly dense but every sentence carries information; no filler.

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?

An output schema exists, so the description rightly does not need to define return values, and it still summarizes them helpfully. However, for a tool with a three-parameter signature whose only complex parameter has zero schema documentation, the description leaves the filter semantics entirely unexplained, which is a material gap.

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 0%, so the description must carry parameter meaning, and it largely does not. `filters` contains eight undocumented fields (people, channels, languages, business_axes, min_confidence, include_legacy, dates, published_to) with no explanation anywhere, and `limit`'s interaction with the 16-source cap is only obliquely hinted at.

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 and resource ('Cross-search summaries and transcript evidence') and a clear scope ('complex business question', 'broad synthesis'). It doesn't name the sibling it is not (find_evidence, search_insights), so an agent must infer the distinction from 'Use this first for broad synthesis'.

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?

Explicitly positions the tool first for broad synthesis, and gives a concrete operating instruction to read `counterpoints` before writing caveats. Missing explicit when-not-to-use or named alternatives, but the sequencing guidance is strong enough for correct selection.

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