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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states that the tool returns matching records with expiry and status, but it does not explicitly declare that the operation is read-only, nor does it disclose potential side effects, permissions, or rate limits. The behavior implied is safe, but not explicitly stated, leaving the agent to infer safety from the verb 'search'.

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 sentences with no redundant words. The purpose is front-loaded, and the return information is concise. Every word contributes to understanding the tool, making it an example of efficient structure.

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 single-parameter search tool with no output schema, the description covers the essential invocation details: what it searches, what it returns. The parameter schema fills the remaining gaps (omit to list everything). It does not mention pagination or limits, but these are not critical for a simple search tool in this context, so the description is largely complete.

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?

The schema already documents the query parameter with 100% coverage, including case-insensitivity and shorthand examples. The description adds meaning by specifying that the query can match 'prescriber name, registration type, or location', which clarifies the search scope beyond the schema's 'prescriber or registration'. This additional semantic detail earns a score above the baseline of 3.

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 states a clear purpose: 'Search controlled substance registrations by prescriber name, registration type, or location.' This specifies the verb, resource, and search dimensions, distinguishing it from siblings like get_registrations_expiring (expiring records) or export_registration_report (export). It is unambiguous and directly conveys what the tool does.

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 description implies usage for general searching but does not explicitly say when to use this tool instead of alternatives, nor does it mention exclusions or alternative tools. There is no guidance on when to prefer a sibling tool, so usage context is only implicit.

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