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

The readOnlyHint annotation already establishes that this is a safe read operation. The description adds useful context that the id must come from `search` and that the tool is premium-gated, but it does not describe return behavior, failure modes, or auth requirements beyond the premium tag.

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 a single efficient sentence with the key constraint front-loaded. The unexplained `[Premium]` label adds slight ambiguity but no verbosity.

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 simple one-parameter read tool with annotations, this is minimally adequate. However, it leaves ambiguity about the `[Premium]` requirement and how this tool differs from `get_listing`, which matters given the crowded sibling set.

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 0%, so the description must carry parameter meaning. It does explain that `id` is a listing id returned from `search`, which is useful provenance, but it does not specify format or clarify whether this is the same id used by sibling listing tools.

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 specific verb and resource: fetch one listing by id. It also clarifies that the id comes from `search`, but it does not distinguish this tool from sibling `get_listing` or explain the `[Premium]` qualifier.

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?

Usage is implied by requiring an id returned from `search`, so the agent can infer it should search first. However, it does not say when to use this instead of `get_listing` or other listing retrieval siblings.

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