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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the description is not the only safety signal. It adds value beyond them by stating the auth requirement ("requires read scope") and by disclosing which fields come back, but says nothing about behavior for missing contacts or contacts with no handles set.

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 terse clauses with zero padding, and the returned field set is front-loaded. The phrasing is sentence-fragment shorthand and the clause "verify a handle write landed" is slightly cryptic in isolation, but no sentence is wasted.

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, annotated, read-only getter with no output schema, it covers the essentials: what is returned, that it is read-scoped, and one motivating use case. It leaves unaddressed what the response looks like when no handles exist and how it relates to get_contact, which a caller would need to know.

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%, with the single `id` parameter documented as "contact ID" in the schema, so the schema carries parameter meaning on its own. The description adds no format, lookup, or error semantics beyond that, which is the expected baseline here.

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 names the specific resource and scope: the contact's social handles, enumerated as instagram/twitter/tiktok, which distinguishes it from the broader get_contact sibling. It is a lowercase noun fragment with no verb ("get"/"retrieve"), so the action is implied rather than stated, but the returned data is 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?

It offers one concrete use case ("verify a handle write landed"), which is a real when-to-use signal. However it never contrasts with get_contact or update_contact, so an agent still has to infer whether to call this or the full contact getter to inspect handles.

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