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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds the multi-vertical qualifying criterion and the lookback-window scoping, but says nothing about result ordering, pagination, or the server-side cap noted in the schema.

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 sentences with no filler, and the core behavior (what the feed lists and under what condition) is front-loaded before the usage hint.

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?

There is no output schema, so the description could have said more about the shape of the returned entity list (fields, ordering). Still, for a zero-required-parameter discovery feed whose annotations already cover safety, it gives enough to call the tool correctly.

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 all three parameters (days, limit, min_verticals) are fully documented in the schema, including defaults, maximums, and the server cap on limit. The description only echoes the lookback window and the 2+ vertical threshold, adding no syntax or format detail beyond the schema. 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?

The description states a specific verb and resource (list of entities with activity in 2+ regulatory verticals) and names the exact scope (SEC + FDA + contracts, inside the lookback window). It also distinguishes itself from the full-timeline sibling by framing itself as a discovery feed.

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 gives a clear when-to-use: 'Use to find entities worth pulling a full cross-vertical timeline for,' which implicitly routes to the entity_timeline sibling. It stops short of naming that sibling explicitly or stating when not to use this feed (e.g., single-vertical lookups).

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