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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is fully covered. The description adds little beyond restating a GET endpoint path: it says nothing about pagination, result volume for receivers with many lines, or how the detail level changes payload size, which is the one behavior an agent would want to know here.

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 resource and followed by the endpoint. Nothing is padded, though the endpoint echo is arguably the least useful of the two sentences.

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 two-parameter read with full schema coverage and read-only annotations, this is close to sufficient: an agent can call it correctly. What is missing is the sibling routing and any hint about output shape or size, which matters because there is no output schema.

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%, so both parameters (including the comma-delimited detail enum) are already documented in the schema. The phrase 'with item details' loosely gestures at the detail parameter but adds no semantics beyond what the schema states; baseline 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?

Names the specific resource (line items belonging to one receiver) and adds that item detail is included, which distinguishes it from extensiv_get_receiver (header data) and extensiv_list_receivers (the receiver list itself). No verb is stated explicitly, but the title supplies 'List' and the identity of the call 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?

There is no when-to-use guidance and no mention of the natural alternatives (extensiv_get_receiver for receiver header data, extensiv_list_receivers to obtain the id). The only routing hint, receiver_id coming from extensiv_list_receivers, lives in the schema rather than the description.

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