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

Annotations already declare readOnlyHint=true, destructiveHint=false, openWorldHint=true, so the safety profile is covered. The description adds the endpoint and notes that requested relations arrive embedded, but says nothing about error behavior for unknown IDs or how the embedded records are shaped beyond the generic 'included' reference.

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 clipped sentences with zero filler; the core purpose and the include behavior are both front-loaded, and the endpoint is appended as a compact anchor.

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 two-parameter read tool with full schema coverage, no output schema, and complete annotation coverage, this is nearly sufficient. The only shortfall is that it does not describe what the returned record or its 'included' relations look like, forcing the agent to rely on the include enum wording.

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 100%, including the enum of allowed include values and the UUID format, so the baseline of 3 applies. The description restates that include controls embedded related records but adds no syntax, defaults, or cardinality detail beyond the schema.

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 ('One user by UUID') plus the include mechanism, and the endpoint reference (GET /users/{id}) confirms single-record retrieval. It implicitly distinguishes itself from the many street_list_* siblings by fetching exactly one user, but never names a sibling explicitly.

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 only implied: 'One user by UUID' signals this is the single-record path versus a list, but the description never says when to prefer it over street_list_users or how to obtain the UUID. No exclusions or preconditions are stated.

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