Get Contact

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

Annotations already declare readOnlyHint=true, so the safety profile is covered by structured data. The description adds only the singular 'one contact' scope and the ID-based access pattern; it says nothing about not-found behavior or what the returned contact contains, so it earns only a baseline-plus score.

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?

A single front-loaded sentence with no filler; the identifier semantics are delivered immediately.

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?

Adequate for a trivial one-parameter read tool with annotations covering safety, but it leaves the routing question (why not contacts_lookup_email/phone) and any failure/lookup semantics unaddressed, which is a real gap given four overlapping siblings.

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% on a single required parameter, but the description labels it 'unified contact identifier', giving the agent the key semantic that this is Apple's unified ID rather than a phone/email. With one parameter and the schema doing none of the describing, this is the minimum acceptable compensation.

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 (Fetch) and resource (one Apple Contact) with the scope qualifier 'by unified contact identifier', which cleanly distinguishes it from the lookup_phone, lookup_email, and search_name 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?

No when-to-use guidance and no mention of the alternatives. An agent must infer that this is the direct-ID retrieval path versus the sibling search/lookup-by-attribute tools; the description does not say so explicitly.

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