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

Annotations already cover the safety profile (readOnly, non-destructive, closed-world), so the remaining burden is modest, and the description does add ordering ('newest first'), an event field list, and the unknown/deleted-ID error. It does not disclose pagination beyond the stated 50-event ceiling or whether results are truncated silently.

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 capability and scope come first, then the event inventory, then sibling routing, then the error case — a well front-loaded structure with no filler sentences. Dense but every clause carries information an agent would otherwise have to infer.

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?

With no output schema, the description compensates by naming the per-event fields (id, type, date, title, summary, metadata) and the error shape. Combined with the annotations and full schema coverage, nothing material is missing for correct invocation.

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 coverage is 100% and the schema already explains the 1-50 limit, the default of 20, the unreachability of older events, and that contactId is a UUID rather than a phone number. The description adds no parameter-level meaning beyond reinforcing 'newest first' ordering, so the baseline of 3 applies.

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 and resource ('Get one contact's full interaction history') and enumerates exactly what is included: calls, SMS, jobs, follow-ups, appointments, notes, document uploads and field changes. It also names the sibling tools it is not (get_contact, getCallDetails, getTextConversation), so the agent can distinguish it without opening any schema.

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?

Gives an explicit decision rule ('what happened with this customer') and then routes three common alternatives to their own tools with the condition that selects each. It also states the failure case ({error: "Contact not found"} for unknown or deleted IDs), which is the kind of edge guidance agents need before calling.

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