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

Annotations already establish the safety profile (readOnlyHint=true, openWorldHint=false), so the operation is known to be a safe local read. The description usefully lists the validation dimensions (required keys, dates, ISO 8601 timezones, transit types, barcodes, color contrast), but says nothing about how failures are reported or what the result looks like.

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?

A single, front-loaded sentence with the verb first and a colon-delimited list of checks. Efficient with no filler; the only minor cost is the dense enumeration of checks.

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 read-only, one-parameter inspector, the description covers purpose, input scope, and validation breadth, and annotations cover the safety profile. With no output schema, the return shape of the validation result is the one unexplained gap.

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 coverage is 100% and the single pass_json parameter is fully documented in the schema, so the baseline is 3. The description adds only mild value by noting it can take pass.json or package manifests, without format or edge-case detail 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?

States a specific verb (inspect and validate) and resource (Apple Wallet .pkpass JSON structure / pass.json or package manifests), and enumerates exactly what it checks. The verb also implicitly separates it from generate/repair siblings, but no sibling is named explicitly, so it stops short of a 5.

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 is only implied: an agent can infer you'd call this when you have a pass.json to check. There is no explicit when-to-use, no when-not, and no routing to alternatives like repair_apple_pkpass_spec (for fixing) or generate_apple_pkpass_spec (for creating).

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