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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, destructiveHint=false), so the bar is lower, and the description still adds non-obvious behavioral facts the annotations cannot: signature/photo links expire in 24 h and the PDF delivery note (ReportUrl) in 1 h. It does not mention permissions or rate limits, keeping it 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 tool's purpose, then a dense but purposeful enumeration of the returned fields, closing with the invocation constraint. Single-sentence density is high but every clause carries information; nothing reads as filler.

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 must describe the return payload, and it does so comprehensively — status plus status time/GPS, signatory, signature and photo links with TTLs, driver comment, reject reasons, quantity comparison, cash, feedback, and the delivery-note link. Nothing an agent needs to call or interpret this result is missing.

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 the baseline is 3, but the description adds a real semantic constraint the schema does not express: the three identity parameters are mutually exclusive and exactly one must be supplied. It adds no format detail for individual fields, which is fine since the schema handles that.

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 a specific verb and resource ('Get the electronic proof of delivery (ePOD) of one order') and immediately distinguishes itself from trackpod_get_order by enumerating the artifact it returns: signatures, photos, delivered vs ordered quantities, cash collected. An agent can tell what this tool produces 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?

The description states the scope ('of one order') and gives a genuine invocation rule — 'Pass exactly one of number, order_id or track_id' — but never names an alternative tool or explains when an agent should choose this over trackpod_get_order or trackpod_find_orders_by_number. Usage is implied rather than routed.

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