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

Annotations provide readOnlyHint=false and destructiveHint=false, already indicating a mutation with no destruction. The description adds significant behavioral context: daily frequency, threshold-based webhook triggering, webhook payload contents (previous/current score, delta, tier change), and the return of a watchId. This goes well beyond the annotations without contradicting them.

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?

The description is composed of five sentences, each serving a distinct purpose: purpose, mechanism, regulatory context, return value, and payload details. While slightly verbose, every sentence adds value, and there is no filler. Front-loading is adequate.

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?

Given the tool complexity (3 params, output schema exists per context signals, annotations present), the description covers core aspects: purpose, trigger conditions, frequency, return value, and payload structure. It omits webhook retry behavior, cancellation method, and concurrency limits, but these are secondary given the output schema likely handles response details.

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%; all three parameters (lei, webhookUrl, thresholdPoints) are documented in the schema. The description does not add new meaning to these parameters beyond referencing thresholdPoints in the webhook condition. It meets the baseline but provides no extra value for parameter understanding.

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 uses a specific verb-resource pair: 'Register an entity for ongoing ESG monitoring.' It clearly distinguishes this from sibling tools like esg.score (one-time score), esg.trend (historical trend), and esg.batch (batch operations) by emphasizing 'ongoing' and webhook-based alerts.

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?

The description implies usage for continuous monitoring needs (daily checks, webhook on threshold) but does not explicitly state when to use this tool versus alternatives like esg.score or esg.portfolio. No exclusions or prerequisite conditions are given, so it's clear but not comprehensive.

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