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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds no behavioral context beyond the directive—no mention of what fields are searched, whether matching is fuzzy, or any special limitations.

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?

The description is a single short sentence with no fluff, which is structurally clean. However, it is under-specified rather than merely concise—it states the action but omits critical details, so it does not earn a higher score.

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?

There is an output schema, so return values are covered, and the annotations handle safety. Yet the description lacks any detail on search behavior, parameter semantics, or differentiation from sibling tools. For a simple two-parameter tool, it still feels incomplete.

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 0%, so the description carries the full burden of explaining 'query' and 'limit'. It does neither, leaving the agent to guess what a query string should contain (name, email, phone?) and how limit affects result ordering or pagination.

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 clearly states a search operation on contacts with a verb and resource, making the primary purpose unambiguous. However, it does not distinguish this tool from siblings like list_contacts or get_contact, which reduces its differentiating clarity.

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 provides a clear usage context: 'Search contacts before selecting a contact ID' implies a prerequisite lookup step. This gives the agent a specific scenario, but it does not mention alternatives or when not to use it, so it lacks explicit exclusions.

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