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

Annotations already cover the read-only/non-destructive profile, and the description adds real value on top: it lists the returned item fields, explains that resultsInfo carries totalCount/hasNext/nextIndex, and specifies passing nextIndex as `page`. It omits rate limits, filter-combination semantics (AND vs OR), and default sort behavior, so not a 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?

Three dense sentences, front-loaded with the core action and default behavior, then return shape, then pagination. Minor waste in the parenthetical '(ContactInfo)' and the vague 'newest filters first' phrase, but overall efficient.

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 22-param, zero-required list tool with no output schema, the description covers return contents and pagination adequately. Gaps remain around filter combination logic and default sorting, but the essentials for correct invocation are present.

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 68% over 22 parameters, so the baseline is 3. The description only reinforces the `page` paging contract (already in the schema) and lists return fields rather than clarifying filters like subscribed, contact_type, or how sort_by/sort_direction interact, so it adds little per-parameter meaning.

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+resource (search/list contacts) with scope ('people and organizations') and the default no-filter behavior, which clearly separates it from get_contact or create_contact. It does not explicitly name a sibling or route between list vs search_deals-style tools, so it stops short of a 5.

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 one useful usage rule — with no filter it returns all contacts — and explains how to continue paging, but never says when to prefer keyword search over structured filters, when to use this vs get_contact, or any exclusions. Usage is implied rather than guided.

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