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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=false), so the description only needs incremental context. It adds real behavioral value by disclosing data freshness ('nightly') and the fixed 7-day window, which an annotation cannot express. It does not mention rate limits or result size, so it stops short of a 5.

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?

Front-loaded with the USE WHEN trigger and only three sentences total, so every sentence earns its place. The trigger list trails off with an ellipsis ('identity signal…'), which is slightly loose, and the 'nightly / last 7 days' detail sits after the trigger rather than up front.

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?

An output schema exists, so return-value detail is not required, and the required 'container_id' is fully documented in the schema. The description supplies the trigger context, the data window, and the routing alternative. It could be marginally stronger by noting the Insights are scoped to a single container.

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%, including the enum semantics for 'view' (report vs metrics) and the meaning of 'detail', so the schema carries this dimension. The description adds no parameter-level detail beyond that, which is the expected baseline when the schema is complete.

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 ('Returns Tracklution's nightly Insights') with an explicit scope window ('last 7 days'), which distinguishes it from the sibling get_summary. An agent can identify the tool without opening the 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?

Opens with an explicit 'USE WHEN' trigger list (tracking health, data quality, consent, ad blockers, bots, identity signal) and names the alternative for a different case: 'For raw totals over a custom date range use get_summary.' Both the when and the when-not are stated.

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