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

Annotations already declare readOnlyHint=false, idempotentHint=false, and destructiveHint=false, so the safety profile is covered. However the description adds nothing beyond them: it does not say what happens if the schema name already exists, whether the operation fails or is a no-op, or what permissions are needed — meaningful gaps for a non-idempotent mutation.

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?

A single well-formed sentence with the resource front-loaded and zero filler. It is efficient, though its brevity edges toward under-specification rather than optimal density.

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?

An output schema exists and both parameters are fully documented, so return values and inputs need no explanation. What is missing is mutation-specific context — failure behavior on duplicate names and Cloud-enablement prerequisites — which leaves the definition merely adequate for a create operation.

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%, with both project_id and name documented including a length bound and an example, so the baseline of 3 applies. The description contributes no additional meaning about parameter semantics.

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 gives a specific verb and resource ('Create a Postgres schema') scoped to the project's Cloud database, which cleanly separates it from siblings like projects_cloud_database_query, projects_cloud_database_tables, and projects_cloud_database_row_insert. It is clear without needing to open the schema, though it does not name any 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?

There is no guidance on when to use this versus alternatives, and no prerequisites are stated — notably that Cloud must already be enabled (projects_cloud_enable) and that a project_id is required. The agent must infer all preconditions from sibling names and the schema.

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