Get a note

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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds a genuinely useful non-obvious behavior: it returns `{ note: null }` when no note exists, which an agent cannot derive from annotations or the input schema. It does not, however, describe the populated return shape or any auth scope.

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, zero filler, with the core action stated first and the edge-case return value second. Every clause earns its place.

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 no output schema, the description usefully documents the empty-return behavior, and the single 100%-covered parameter needs no further explanation. It stops short of sketching the success shape, which would have made it fully self-sufficient.

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%, so the id parameter is fully documented in the schema (pattern, minLength, description). The description only adds the parenthetical list of entity kinds, which is marginal value beyond the schema. 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?

Specific verb+resource+scope: 'Read the note attached to an entity ... by its id.' It is clearly distinguishable from the write-side sibling update_note, though it never names that sibling explicitly. Purpose is unambiguous without opening the schema.

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 'Read the note' and the field-level id reference, and the read-vs-update split against update_note is inferable, but there is no explicit when-to-use or when-not-to-use guidance. Adequate minimum but with a clear gap.

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