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

Annotations already declare readOnlyHint=true, so safety is covered. The description adds genuinely non-obvious behavior: that reads are implemented as 'POST /customers/search' and that only a SINGLE field/operator/value clause is supported (AND-comparison only), which is a real constraint an agent must respect.

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: the first front-loads what the tool does, the second enumerates the three optional capabilities plus the backing endpoint. No filler, no repetition of 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 an all-optional, 7-parameter search tool with no output schema, the description covers filtering, sorting and pagination adequately. It stops short of noting default or maximum limit behavior and gives no hint about what customer fields come back, which a fully complete definition would include.

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 seven parameters are already documented in the schema with examples and enums. The description only restates the filter/sort/paginate grouping and adds that field+operator+value form one clause; it contributes little beyond the schema, so the baseline of 3 applies.

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 ('List / search customers') and immediately disambiguates the resource with a parenthetical ('people who chatted in'). It implicitly separates itself from the singular helpcrunch_get_customer, though it never names that sibling.

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 describes the optional capabilities (single filter clause, sort, pagination) so an agent can infer how to use it, but it never states when to reach for this tool instead of helpcrunch_get_customer or helpcrunch_list_chats, nor any exclusions or prerequisites.

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