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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds real behavioral value by disclosing the conditional expansion with includeFields=true, but says nothing about result size, pagination, or ordering for large schemas.

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 short sentences, front-loaded with the core action and followed by the conditional behavior. Efficient overall, with only a mild parenthetical about AI usefulness that is slightly meta rather than instructional.

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 read-only list tool with full schema coverage and no output schema, the description covers the key variable output mode (with/without fields). It does not sketch the returned entity shape or field-level detail, but the omitted pieces are minor for a listing tool.

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%, so both parameters are already documented in structured form; baseline 3 applies. The description reinforces includeFields semantics but adds no syntax or format detail beyond the schema, and expectedProjectId's override/refusal behavior is left entirely to the schema text.

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?

Names a specific verb and resource ('Lists the ERD entities of the project') and scopes it to the current project. It is clear what the tool returns, though it does not differentiate itself from potential siblings such as get_schema_overview or analyze_data_model.

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?

Provides an implied usage cue ('useful for the AI when it wants to understand the existing data schema') tied to includeFields=true, but offers no when-not guidance and never names an alternative tool for schema inspection. Usage is inferable rather than stated.

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