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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds only a templated pricing estimate ($0.075/credit) — marginally useful cost context, but no operational behavior about the segment-analysis call itself (e.g., what the segment ID requirement implies, latency, or result shape).

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?

It is short, but every sentence is boilerplate pricing metadata that does not earn its place against the tool's actual purpose. Brevity here reflects under-specification, not conciseness.

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 9-parameter, 5-required analytical tool with no output schema and 22% schema coverage, the description is completely inadequate — it omits purpose, usage, parameter meaning, and return expectations entirely.

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 only 22% and the description adds nothing about the 9 parameters — not the comma-delimited metrics delimiter, not the date range semantics, not granularity or main_domain_only. The one genuinely tricky parameter (segment ID) is documented only in the schema, not the description.

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 contains no statement of purpose at all — it is exclusively a pricing/billing block. The title 'Segments Marketing Channels' hints at the domain, but the description itself never says what the tool does, and it cannot be distinguished from sibling segment/keyword/website analyst tools from the description text.

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?

There is no when-to-use guidance, no prerequisites, no exclusions, and no reference to any alternative sibling tool. The agent receives zero routing information from the description.

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