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

readOnlyHint=true already tells the agent this is a safe read, so the description only needs to add beyond that. It contributes the underlying API path (GET /api/4/customers), which helps an API-aware agent map to docs, but stays silent on pagination limits, total-count behavior, or rate limiting — the traits that actually matter for a list endpoint.

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 short sentences, front-loaded with the operation and its filters. The trailing endpoint reference is compact and optionally useful rather than filler, though it is the least agent-relevant clause.

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?

Eight parameters but all documented at 100% coverage in the schema, and no output schema means return shape is out of scope for the description. Combined with readOnlyHint covering the safety profile, the definition is adequate; only the absence of any result-count or pagination guidance keeps it from a 5.

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 eight parameters (q, tag, page, sort, email, include, archived, page_size) are already self-documenting. The description's summary list duplicates those fields at a higher level without adding format details (e.g. how sort syntax interacts with pagination), so baseline 3 is appropriate.

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 gives a specific verb+resource (list customers) and enumerates the search/filter dimensions, plus the underlying endpoint. It stops short of explicitly distinguishing itself from siblings like booqable_get_customer or booqable_create_customer, so the scope is clear but not sibling-differentiated.

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 implied by 'List customers' — the agent can infer this is the collection endpoint versus booqable_get_customer for a single record, but the description never says so. No when-not-to-use guidance, no prerequisites, and no mention of pagination behavior for a list of potentially hundreds of customers.

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