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

Annotations already declare destructiveHint=true and idempotentHint=true, so the bar is lower, yet the description adds irreversibility ('permanently') and a concrete business-rule constraint about locked/reserved photos. It omits permission/auth requirements, which the guestToken parameter hints at but the description never addresses.

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 tight sentences, with the destructive action and its key constraint front-loaded. Every clause carries 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?

Output schema exists, so return values need not be explained, and annotations carry the safety profile. What remains missing is the auth path (guestToken vs Authorization Bearer) for a destructive operation, which matters for correct invocation.

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 50%: photoId has no description at all, and only guestToken is documented in the schema. The description mentions no parameters, so it does nothing to compensate for the undocumented photoId or to clarify the guestToken-vs-Bearer auth choice.

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?

States a specific verb ('permanently delete') and resource ('one of your uploaded photos'), with the scope limited to a single photo the caller owns. No sibling tool deletes photos, so the agent can distinguish it from get_photo/list_photos without opening a schema.

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?

Gives an explicit exclusion: photos locked or reserved by an order cannot be deleted, which tells the agent when the call will fail. It does not name alternatives or describe the intended workflow (e.g., check get_photo first), so it stops short of full when/when-not guidance.

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