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

Annotations already declare the safety profile (not read-only, non-destructive, idempotent, closed-world), and the description adds genuinely new context: sign-in is required, the effect is scoped to this buyer, and subsequent searches/listings will include the collection. It does not cover what happens on a wrong or expired code, which is the main remaining gap.

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?

Front-loads what the tool does, then the example, then the observable effects, then the usage constraint and auth requirement. Every sentence carries information an agent needs; nothing is padding.

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?

With annotations, an output schema, and full parameter documentation already present, the description covers purpose, auth, post-state, and the caution against guessing. Only failure semantics for an invalid code are left unaddressed.

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% and both parameters are described there, including accepted address formats for 'gallery'. The description only loosely restates their provenance ('the address and access code its photographer gave them'), adding little beyond the schema, so baseline 3 applies.

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 and resource (open a PRIVATE collection to the signed-in buyer) plus the mechanism (address + access code from the photographer). The wedding/client-gallery example makes the domain concrete, and no sibling tool does anything similar, so it is unambiguous against the list.

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 when-not: only with a code the person supplied, never guess one. It also explains the payoff ('afterwards search_images, get_image and list_collections include it') so the agent knows why and when to call it relative to sibling retrieval tools.

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