get_contact

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

Annotations already declare readOnlyHint=true, destructiveHint=false, and idempotentHint=true, so the safety profile is clear. The description adds the capability to retrieve by ID or email, but does not elaborate on any behavioral nuances such as rate limits, data freshness, or error cases. Given the annotation coverage, the description adds moderate but not extensive transparency.

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 sentence that immediately conveys the action and valid identifiers. It is front-loaded, concise, and contains no superfluous information, making it efficient for an agent to parse.

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 simple retrieval tool with one parameter and rich annotations, the description adequately covers the core function. However, it does not mention what data is returned (e.g., full contact object) or any response structure, but this is typical for get operations and is partly compensated by the tool name and schema.

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 input schema already describes the 'id' parameter as 'Contact ID or email address' with 100% coverage. The description essentially restates this information without adding new semantics, such as format expectations or behavior when both types are provided. Thus, it meets the baseline but does not exceed it.

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 'Retrieve a contact by ID or by email address,' specifying the verb (retrieve) and the resource (contact). It also distinguishes from sibling tools that deal with properties, segments, or other resources, making the purpose unambiguous.

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 provides no explicit guidance on when to use this tool versus alternatives like list_contacts or get_contact_property. It does not mention conditions, prerequisites, or scenarios where this tool is preferred, leaving the agent to infer usage without clear heuristics.

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