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

Beyond annotations (readOnlyHint=true), the description discloses pagination support, type filtering, and the exact fields returned including type-specific fields. This gives agents a complete picture of the return payload and behavior without an output schema.

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 front-loaded with the main purpose and includes useful examples. The field list is somewhat lengthy but serves as a substitute for an output schema, so it 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?

For a read-only list tool with no output schema, the description sufficiently explains the return fields, filtering, and use cases. It is complete enough for an agent to invoke correctly without additional context.

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%, with each property already documented. The description only restates that pagination and type filtering are supported, adding no extra meaning over the schema. 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 clearly states the tool returns gallery items from the authenticated user, listing exact media types (images, videos, audio). It distinguishes itself from sibling generation/edit tools by being the listing tool for user creations.

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 provides explicit example workflows ('find my last 5 images and reframe them', 'list my recent songs and master each one'), indicating when to use this tool before editing. It lacks an explicit 'when not to use' but there are no sibling listing tools, so context is clear.

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