image_registry_data

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

Annotations already indicate read-only and non-destructive behavior, and the description adds substantial context beyond that: the tool does not pull the image, it relies on the daemon's cached credentials, and it warns that `auth_config` may be logged verbatim. This disclosure of internal mechanism and security implications exceeds what annotations provide.

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 well-structured with separate paragraphs for purpose, usage, security, and argument documentation. Every sentence adds value, but the multi-paragraph format is slightly more verbose than necessary. The front-loaded first sentence conveys the core purpose immediately.

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?

Given the tool's simplicity (2 params, read-only, no output schema), the description is complete: it explains the operation, the return dict structure, the dependency on the daemon, the alternative tool, and security considerations. No critical aspects are missing for an agent to invoke it correctly.

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?

With 0% schema description coverage, the description compensates with brief but meaningful explanations: 'repository - Image reference' and 'auth_config - Optional registry authentication config.' It also adds a security note that clarifies how to treat auth_config. While the parameters are not deeply detailed, the description provides adequate meaning for the agent to use them correctly.

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 clearly states the tool's purpose: 'Get registry data for an image without pulling it, via the daemon's distribution endpoint.' It identifies the specific resource (image registry data), the operation (get), and the method (daemon distribution endpoint). It also distinguishes itself from sibling tools like `registry_manifest` by specifying the daemon-dependent approach.

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 explicitly provides usage context and an alternative: 'For direct registry access without a daemon use `registry_manifest`.' It also gives security guidance on when to use `auth_config` and recommends leaving it unset in favor of `docker login`, which helps the agent decide how to invoke the tool.

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