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

Annotations already declare readOnlyHint=true, so the safety profile is covered; the description usefully adds the pagination contract (paginated, max 50 per page). It says nothing about default page size, sort order, or total-count behavior, which would help an agent page correctly.

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 tight sentences with zero waste, front-loading what is listed and then the filtering and pagination constraints. Nothing is padded or restated from the title.

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 6-parameter, read-only list tool with no output schema and low schema coverage, the description covers the essentials (filters, pagination cap) but omits what a contact record returns, default paging behavior, and how filters combine. Adequate but with noticeable gaps.

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 17% (only 'q' is documented in the schema), so the description carries real weight here: it maps tag, list, and email consent status to tagId/listId/status and mentions the 50-per-page cap for pageSize. It still leaves the page parameter and the meaning of the three consent-status enum values unexplained.

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?

States a specific verb and resource ('Lists the workspace contacts') and adds the supported filtering modes (text search, tag/list/consent-status filters), so it is clearly distinguishable from the singular get_contact. It never names a sibling tool or explains scope boundaries against the many other list_* tools, so it falls short of the top mark.

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?

Usage is only implied: the enumeration of 'quick filters' suggests this is for browsing/filtering contacts rather than segment-based or single-contact retrieval, but the description never says when to choose this over get_contact, create_segment, or list_lists. No exclusions or prerequisites are given.

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