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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered; the description adds genuinely new behavior context: this is a legacy v1-API path and its return payload is a subset of get_event's (missing page URL and destinations). It does not discuss error behavior for invalid ids, but an output schema exists to carry return shape.

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, both earning their place: the first fixes the name/purpose mismatch, the second routes to the preferred sibling. Legacy status is front-loaded.

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 full schema coverage, an output schema, and clear annotations, the remaining burden is orientation — and the description meets it by flagging legacy status and the get_event alternative. A slightly firmer deprecation/selection rule is the only thing missing.

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 all three parameters (including the evt_/TE id formats and the multi-server container constraint) are already documented in the schema. The description only references the id formats the schema already explains, adding no syntax or semantics beyond it — 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?

The description states a specific verb and resource — returns ONE event by its id — and explicitly corrects the misleading 'list' name by emphasizing single-item retrieval. It also names the sibling get_event and distinguishes scope, so an agent can tell them apart without opening either 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?

Labeling it a 'Legacy tool' plus noting that get_event returns the same event with its page URL and destinations strongly steers the agent toward the non-legacy alternative. It stops short of an explicit 'prefer get_event unless X' rule, so it's clear context rather than a hard when/when-not directive.

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