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

readOnlyHint=true already tells the agent this is a safe read, so the burden is lower. The description does add value by listing the returned field groups, which matters given there is no output schema, but it says nothing about not-found behavior, error handling, or authentication requirements.

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 tightly-packed sentences: the return payload first, then the underlying endpoint mapping (GET /events/{id}). No filler, and the most decision-relevant information 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?

For a one-parameter read tool with no output schema, the description compensates well by enumerating returned fields, and the included API endpoint aids disambiguation. It falls short only on failure modes and lifecycle details, which are minor here.

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?

With a single parameter at 100% schema description coverage, the schema fully documents event_id. The description adds no format, source, or constraint detail beyond what the schema already provides, which is the expected baseline.

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 specific verb and resource ('Fetch one event') and enumerates the fields returned (name, summary, dates, location, capacity, category, campaign, registration and financial settings), so the agent knows exactly what it gets back. It implies single-record scope versus the neon_list_events sibling, but never names that sibling explicitly to differentiate.

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 word 'one' implies this is for retrieving a single known event rather than enumerating, which nudges toward neon_list_events for browsing. However, there is no explicit when-to-use or when-not-to-use statement, no mention of prerequisites, and no reference to alternatives.

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