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

Annotations already declare readOnlyHint=true, openWorldHint=true, and idempotentHint=true, which cover safety and side-effect behavior. The description adds content-level detail about the metrics returned (follower growth, engagement, demographics, page views) but nothing beyond that—no auth requirements, rate limits, or pagination notes. Given the annotations, a 3 is appropriate: the description supplements but does not deeply extend the behavioral profile.

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 exactly two sentences, front-loads the purpose, and wastes no words. The primary function is stated first, followed by the data types and a direct suggestion to use a sibling tool. Every sentence earns its place, making it optimally concise and well-ordered.

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 read-only tool with no output schema, the description adequately covers what the tool does, what it returns, and how it fits into a workflow (comparison with profiles). It does not explain return format or pagination, but given the tool's simplicity and the sibling tool reference, the context is sufficiently complete for an agent to invoke it correctly. A 4 reflects minor missing details (like return shape) that are not critical.

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 four parameters (profile, organization_id, start_date, end_date) are already documented in the input schema. The description adds a hint about parameter usage ('same period as the personal profiles'), which subtly advises aligning dates, but it does not elaborate on parameter syntax or relationships beyond what the schema already provides. Baseline 3 fits.

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 the specific resource ('company page'), the action ('fetch company page reach'), and the data fields (follower growth, engagement, demographics, page views). It also explicitly names the sibling tool 'get_profile_performance' and contrasts the two, making the purpose unambiguous and distinct from siblings.

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 a clear usage directive: 'Use alongside get_profile_performance to show how the team's profiles compare against the page.' It implies when to use this tool (alongside the profile performance tool) and the context (comparison). It does not explicitly state exclusions from other analytics tools, but the cited sibling is the most relevant alternative, so it earns a 4.

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