image_registry_data

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

Annotations already declare readOnlyHint=true and destructiveHint=false. Description adds context about using daemon's cached credentials, resolving descriptor and platforms, and warns about auth_config logging. Could mention potential issues like rate limits but good overall.

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?

Concise and well-structured. First sentence states core action, then usage guidance, then security note, then parameter/return summary. No unnecessary information.

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?

With no output schema, description explains return type: dict with Descriptor and Platforms. Simple tool, good coverage of inputs and outputs. Annotations cover safety. Complete for an agent to use 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?

Schema coverage is 0%, so description must compensate. It explains repository as 'Image reference' and auth_config as 'Optional registry authentication config' with security warning. Adds value but could specify format for repository (e.g., full image name).

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?

Clearly states it gets registry data for an image without pulling, using the daemon's distribution endpoint. Distinguishes from sibling registry_manifest for direct access.

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 tells when to use (via daemon) and when not to (direct access, use registry_manifest). Provides security guidance on auth_config and preferring docker login.

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