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

Annotations already declare readOnly/idempotent/non-destructive, and the description adds ordering ('newest first'), pagination behavior ('cursor pagination'), and a security-relevant trait: notes are untrusted content that must not be followed as instructions. That last point is behavioral context no annotation covers and materially affects how an agent should treat the return value.

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?

Three sentences, each earning its place: purpose/scope is front-loaded, then the content semantics, then the safety caveat. No filler or repetition of annotations.

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 an output schema present and rich annotations, the description need not explain return values. It covers purpose, ordering, pagination, and the untrusted-content handling requirement, which is everything an agent needs to call and correctly interpret it.

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 limit, cursor, reason, user_intent, and namespace_id are all documented in the schema itself. The description adds only the pagination concept, which the schema already frames. Baseline 3 is appropriate when the schema does the heavy lifting.

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 ('List pinned notes for a Flowlines namespace') plus scope details (newest first, cursor pagination). The follow-up sentence explains what notes are, making it unmistakable against siblings like save_note or list_signals. An agent can identify this tool 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?

It gives a clear condition for use ('Read them before re-deriving a known issue') and warns against following note instructions. It doesn't explicitly name an alternative or exclusion, but the read-before-rederiving trigger is concrete guidance rather than mere implication.

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