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

With no annotations at all, the description's opening 'Read-only' is genuinely valuable because it establishes safety and no side effects. It also explains what only_with_email=false actually counts. Beyond that it says nothing about cost, whether the search must be active, or what happens on an invalid search_id, so the burden of full behavioral disclosure is only partly met.

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?

Three short sentences with the read-only safety note front-loaded and no filler. The phrasing 'what outreach "Who to contact" uses' is compact but leans on an external UI reference an agent may not know, slightly reducing clarity per word.

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 and no annotations, so the description has to carry the full load. It conveys the four buckets and the mode switch, which is broadly sufficient to call the tool, but it does not describe the shape of the returned counts (field names, whether unchecked is always present) or prerequisites such as the search existing.

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 0%, so the description must compensate for both parameters. It gives real semantics for only_with_email (false counts email-or-LinkedIn reachable contacts, matching outreach behavior), which is more than the schema offers. search_id, the required identifier parameter, is never described or constrained, leaving half the parameters undocumented.

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: it returns counts of contacts bucketed as Fit, Uncertain, Not a fit, and unchecked. That is distinguishable from siblings like sdr_persona_stats or sdr_overview. It never explicitly says the counts are for a given search, which the required search_id implies but the text leaves implicit.

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 line 'Use before choosing icp_segment' gives a forward-looking usage cue, and the note about matching outreach's 'Who to contact' view helps an agent pick the right mode. However, icp_segment is not a sibling tool name, and the description never says when NOT to use this (e.g., versus sdr_get_search or sdr_persona_stats), so the guidance is suggestive rather than explicit.

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