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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered; the description adds real value by disclosing the exact payload contents, including that manifest id/number only appear once booked. It does not discuss error behavior for an unknown tracking number.

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 purpose and field list, then the negative-scope note. The trailing 'GET /orders/{tracking_number}' endpoint string is redundant filler for an agent that already has the schema.

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 enumeration of returned fields carries the burden well, and the booking-state caveat on manifest fields prevents false expectations. Only failure modes and format details are 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% and already documents the tracking number format and origin, so the description adds nothing new beyond repeating 'by tracking number'. 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?

States a specific verb and resource (retrieve a single Shippit order) and enumerates exactly which fields come back. It also explicitly notes there is no list-orders endpoint, which cleanly separates it from the listing-style siblings.

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 note that no list-orders endpoint exists tells the agent this is the only lookup path, and the tracking_number requirement makes the prerequisite clear. It does not, however, contrast itself with shippit_get_tracking, which an agent could easily confuse it with.

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