track_package

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

Annotations already declare readOnlyHint=true and idempotentHint=true. The description adds valuable behavioral context by stating it auto-detects carriers, returns current status and recent tracking history, and warns about Amazon TBA numbers not being supported. This goes beyond the annotations and does not contradict them.

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?

The description is two sentences plus a note, front-loaded with the primary purpose. Every sentence is informative with no wasted words, covering action, behavior, output, and a limitation in a compact form.

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 simple one-parameter read-only tool, this is complete enough: it states the input, behavior, and output overview, and flags the important Amazon TBA limitation. Without an output schema, it could specify the return format in more detail, but it provides a reasonable high-level as-is.

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?

The input schema fully describes the single 'tracking_number' parameter with carrier list, so schema coverage is 100%. The description's mention of auto-detection aligns with the schema but adds no extra parameter syntax or format details. A baseline 3 is appropriate since the schema carries the semantic load.

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 uses a specific verb 'Track' with resource 'a package' and clarifies scope 'by tracking number'. It clearly distinguishes from all sibling tools, which are system monitoring and file operations. Mentions carrier auto-detection and return of status/history, fully defining the tool's unique purpose.

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 clearly implies when to use (any package with a tracking number) and explicitly excludes Amazon TBA numbers, directing users to track those elsewhere. It does not name an alternative tool among siblings, but the Amazon note serves as a specific when-not-to-use condition, providing adequate usage guidance.

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