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

Annotations already cover readOnlyHint, destructiveHint, and openWorldHint, so the safety profile is set. The description still adds real value beyond them by disclosing that signal titles/summaries originate from public sources and must be treated as data rather than instructions — a prompt-injection warning the annotations cannot express. It does not discuss freshness beyond the implied weekly cadence or how the verdict is derived, which keeps it below 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?

Purpose and trigger are front-loaded in the first clause, and every routing sentence carries a distinct instruction. The opening enumeration is long but earns its length by telling the agent what the response will contain, though 'Read-only, no parameters' mildly duplicates the annotations and empty schema.

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?

With no output schema, the description must explain the return value, and it does so by listing the five components an agent will receive. For a composite briefing tool that is the essential information; only the shape/nesting of the returned sections is left unspecified, which is a minor gap given the enumerated contents.

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 tool takes zero parameters, so the parameter-semantics baseline is 4, and the description is consistent with the empty schema by stating 'no parameters'. There is no additional parameter meaning to convey, so no further credit is available.

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 names the resource (the account's weekly catch-up) and enumerates its actual payload: weekly verdict, heating/cooling competitors, top signals from the last 14 days, account momentum, and the single best next step. It also explicitly distinguishes itself from get_competitor, get_momentum, and ask, so an agent can pick it without opening any schema.

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 an explicit trigger ('when the user asks what changed or wants an update'), a prerequisite branch ('if the user seems new, call start_here first'), and three named alternatives with the conditions that select them (single competitor, all-competitor momentum, free-form question). Nothing in the routing decision is left to inference.

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