blender_blend_contents

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so safety is covered. The description adds valuable behavioral context by specifying the output contents (user counts, orphans, library info) that an agent would need to decide if this tool fits the task.

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, no fluff, with the core action and output details front-loaded. The usage guidance is appended as a second sentence, keeping the structure efficient.

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 read-only inventory tool with optional parameters and no output schema, the description captures the essential purpose and the type of data returned. It could mention output format, but the response_format parameter already covers that, so it's sufficiently complete.

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 100% – both parameters are described in the schema (types and response_format). The description adds no extra nuance about parameters, so baseline 3 is appropriate.

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 states a clear verb ('inventory') and resource ('every datablock in the file') with specific details (user counts, orphans, library origin). It distinguishes itself from siblings like blender_list_libraries by focusing on datablock-level inventory rather than library-level listing.

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?

It provides explicit context: 'before merging or cleaning it' – a clear when-to-use scenario. However, it does not name alternatives or explicitly state when not to use it, though the 'fastest way' phrasing implies preference.

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