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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so the safety profile is covered. The description adds real value beyond that: it states that each part of the code is explained and, importantly, discloses a capability boundary (no product lookup), which prevents an agent from misusing the result as a product resolver.

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 sentences with no filler: the capability and its scope come first, and the limitation follows. Every clause earns its place and nothing is repeated from the schema or annotations.

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 one-parameter, read-only inspection tool with full schema coverage and clear annotations, the description covers what it does, what it accepts, and what it cannot do. The only mild gap is that there is no output schema, and "explains each part" only loosely sketches the return shape.

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?

There is a single parameter and schema description coverage is 100%, with the schema already supplying a concrete example ("LPN RR AB1234567"). The description reinforces that the input is the code exactly as printed on the sticker, which is mildly useful, but it adds no format, normalization, or whitespace-handling details beyond the schema.

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 names a specific verb and resource ("Read the code from an Amazon sticker") and enumerates exactly which sticker code types it resolves (LPN, FNSKU, ASIN, FBA box label, Amazon Logistics tracking number, UPC/EAN). However, it never distinguishes itself from the sibling tool identify_code, whose name suggests a very similar role, so an agent cannot pick between them from the description alone.

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?

Usage context is implied by "from an Amazon sticker" and one explicit exclusion is given: it cannot look up which product a code belongs to. What is missing is routing guidance — if a code is a generic retail barcode rather than an Amazon sticker, the description does not point the agent to identify_code, parse_gs1, or convert_upc_e.

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