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

Annotations already establish readOnly/non-destructive/openWorld, so the description's contribution is the page size (50 per page) and the account-wide scope, both of which are operationally useful and not in the structured fields. It does not mention matching semantics (partial vs exact, case sensitivity), which would be the next valuable disclosure.

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 with the scoping detail front-loaded. The trailing 'GET /subscribers/search_by_name' is largely redundant for an agent and is the one element that doesn't clearly earn its place.

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 two-parameter read tool with full schema coverage and no output schema, the definition covers scope, page size, and pagination intent sufficiently to call it correctly. Only the match semantics of 'name' remain unstated.

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% — both 'name' and 'page' are documented, including the next_page chaining hint. The description adds only the implicit page size of 50; baseline 3 is appropriate where the schema does the work.

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 subscribers by name') and adds scope ('across all campaigns of the account'), which distinguishes it from list_subscribers and from the email/referral-code lookups in the sibling set. It stops short of explicitly contrasting itself with those siblings.

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?

The account-wide scope implies when to use it (a name search not constrained to one campaign), but there is no explicit when-not guidance or pointer to get_subscriber_by_email / get_subscriber_by_referral_code as alternatives for exact identifiers.

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