Open a workspace image or ZIP image member

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

The description adds meaningful behavior beyond the annotations: it states supported formats, the 'bounded' size constraint, and that the archive is never extracted to disk. These are useful operational details that the readOnlyHint annotation does not convey.

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?

Two sentences, front-loaded with the return value and formats, and the key behavioral guarantee is stated in one short second sentence. Every word earns its place.

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?

The description explains the return form (MCP image content), supported formats, and the two input paths, which is sufficient for an agent to call the tool correctly. It does not describe error cases, but the schema and annotations cover the essential requirements.

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 four parameters. The description adds context about the two usage modes but does not go beyond the schema's mutual-exclusion notes or parameter meaning.

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 uses a specific verb ('Return') and a precise resource: one bounded PNG/JPEG/GIF/WebP as MCP image content. It also clearly distinguishes the two input modes (direct path vs. ZIP member), which separates this tool from sibling file operations.

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 gives clear context for when to use the tool: when you need an image as MCP content, either from a workspace path or from a ZIP member. It does not explicitly name alternative tools or exclusion criteria, but the direct-vs-archive distinction is actionable.

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