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

Annotations already cover readOnlyHint and openWorldHint, so the safety profile is known. The description adds a genuinely useful cost model ('1 credit per record returned, minimum 2'), which is not in any structured field. It stops short of describing pagination ceilings or rate limits, but the credit-cost disclosure is a strong addition.

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 sentences, front-loaded with the core purpose, then the cost constraint, then routing to alternatives. No redundancy and every sentence carries distinct information.

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?

An output schema exists so return values needn't be detailed beyond the field list already given. With 16 optional parameters fully documented in the schema, the description adds the missing dimensions — cost and sibling routing — leaving nothing an agent needs to call this correctly.

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 every parameter (q, page, sort, filters, page_size, etc.) is already documented by the schema. The description only references page_size and generic 'filters' without adding syntax or default behavior beyond what the schema states. Baseline 3 is correct.

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 (Search) and resource (stored public Facebook Page contact records) and enumerates the returned fields (website, email, phone, WhatsApp, category, like count). It also names the two sibling tools it is not, so an agent can tell it apart from datasets_facebook_pages_item and datasets_facebook_pages_facets immediately.

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?

Explicitly routes to alternatives: 'use datasets_facebook_pages_item for one record or datasets_facebook_pages_facets for counts.' It also advises using filters for contact fields and discovery source, and warns to keep page_size minimal, giving clear when-to-use and how-to-use guidance.

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