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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), yet the description adds real value beyond them: the quota mechanics (10 free + purchased slots), who validates the quota (origin within the transaction), and the behavioral consequence that over-quota watches return `suspensa: true` and generate no email. This is useful context an agent cannot derive from the annotations.

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?

Front-loads the purpose well, but the second and third sentences drift into internal implementation detail (the Worker, the origin transaction flow) that adds length without helping an agent decide or invoke correctly. Tighter phrasing would preserve the useful quota/suspensa facts.

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 no output schema, the description conveys the key result semantics (quota and the `suspensa` flag) an agent needs to interpret output. It is close to complete, missing only explicit sibling routing.

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%; the single `credito` parameter is fully documented in the schema (token from POST /api/credito). The description touches on quota/credit context but adds no syntax or format detail beyond the schema, so 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?

States a clear verb+resource: it lists the CNPJs monitored by the credit portfolio, immediately distinguishing it from the write counterpart add_watch. It does not explicitly name the sibling, but the read/list scope is unambiguous.

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 the name and purpose (fetch the watches you monitor), but there is no explicit when-to-use/when-not guidance or reference to alternatives like add_watch. No prerequisites for calling are stated.

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