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

Annotations already declare readOnlyHint=true, and the description reinforces the read-only nature while adding substantive content disclosure (what fields and lists are returned). With no output schema, this return-content description carries real weight, though it says nothing about pagination limits or result size behavior.

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?

Three tight sentences, front-loaded with the resource and payload before the read-only note and usage routing. Every sentence carries information, though 'Read-only' mildly duplicates the annotation.

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 an eight-parameter read tool with no output schema, the description adequately covers what is returned and how to identify the target. It is complete enough to invoke correctly, with only pagination/limit behavior left implicit.

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 schema already documents all eight parameters, including the enum-like semantics of license_risks, package_types and search. The description's only added parameter meaning is how to identify the image (digest or repo:tag), which the schema also states. 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?

Names a specific verb (Read) and resource (one image's full bill of materials) and enumerates the contents: identity/base OS, workload containers, and components with versions, ecosystems and licences. This clearly distinguishes it from the sibling list/get SBOM tools that operate on components, containers or findings.

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?

Explicitly states the use case ('the tool for licence review and "what is actually inside this image" questions') and routes the agent to list_security_sbom_images for obtaining the image reference. It lacks an explicit when-not/alternative-condition clause, so it falls just short of a 5.

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