Pin a subscriber's location

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

Annotations already declare destructiveHint=true, idempotentHint=false and openWorldHint=true, so the safety profile is partly covered. The description adds value beyond that by naming the blast radius ('delivery, audience membership, published data or irreversible state') and the confirm gate, though 'May affect' is hedged rather than precise.

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 short sentences, front-loaded with the action and followed by impact plus the confirm requirement; nothing is wasted. It is slightly under-specified rather than verbose, which is the right side of the trade-off.

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 6-parameter, nested-object, no-output-schema mutation tool, the description covers the destructive impact and the confirm gate, which are the two things an agent most needs. The remaining gap is the location payload structure, which the schema handles.

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 83%, so the schema already documents subscriber_id, confirm, account, payload and payload_file. The description only echoes the confirm requirement and adds no detail on the location object fields or the payload/location mutual exclusivity, so it is at the baseline.

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 states a specific verb and resource ('Pin a subscriber's location'), matching the title and clearly identifying the operation. It does not name the sibling tools (update_subscriber_location, delete_subscriber_location) it must be distinguished from, but the action itself 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 gives one concrete prerequisite ('Requires confirm=true'), which is genuinely useful for invocation. However, it never states when to prefer this over update_subscriber_location or delete_subscriber_location, nor what conditions make pinning appropriate, leaving the selection logic to inference.

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