image_history

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

The description details the exact fields in each entry (Id, Created, CreatedBy, Size, Comment) and notes order ('newest first'). No contradictions with annotations (readOnlyHint, destructiveHint). Annotations already indicate safe read, and description adds meaningful behavior context.

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 concise (two short paragraphs) with clear structure: purpose, use cases, return fields, alternative. Every sentence serves a purpose with no redundancy.

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 simple tool with one parameter, no output schema, and clear annotations, the description fully covers purpose, usage, return values, and alternatives. No gaps remain.

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?

Even though schema coverage is 0%, the description explicitly documents the single parameter 'id_or_name' with clear semantics: 'Image name (with optional tag/digest) or id'. This adds full meaning beyond the schema's bare type definition.

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 'Return the layer history of an image' using a specific verb and resource. It distinguishes from the sibling tool 'image_inspect' by noting that tool is for full metadata, making the purpose unambiguous.

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 mentions it is 'useful for auditing what commands built each layer and diagnosing image size,' and provides a clear alternative: 'For full image metadata use image_inspect instead.' This gives both when-to-use and when-not-to-use guidance.

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