send_identify

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

No annotations are present, so the description carries the full behavioral burden. It notes the public collection API but omits what the call actually mutates (new session vs. update to an existing one), whether it is idempotent, whether data and distinctId can be sent together, and what side effects or response to expect.

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. Its brevity is appropriate, though it comes at the cost of the missing usage and behavioral detail flagged elsewhere.

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 5-parameter mutation tool with a nested object, no annotations, and no output schema, the description is too thin. It leaves unresolved when to call it, how it interacts with send_event, and what identifying state it sets, which are essential 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 only 60%, and the description adds little beyond it: 'session data' maps to the data object and 'distinct ID' to distinctId, both already described in the schema. The required websiteId and the url/hostname parameters receive no explanation of format or role in the description.

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 gives a specific verb ('Attach') and resource ('custom session data or a distinct ID') and names the public collection API, so an agent can tell what it does. It does not, however, distinguish it from the closest siblings (send_event, batch_events, send_performance), which all go through the same collection pathway.

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?

There is no explicit when/when-not guidance and no named alternative. The agent must infer that this is the user/session-identification counterpart to event-sending tools, with no statement about prerequisites, ordering relative to send_event, or required authentication.

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