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

Annotations already declare readOnlyHint=true, openWorldHint=true and destructiveHint=false, so the safety profile is covered. Beyond that, the description discloses the returned payload (full before/after values) and the conditional behavior of include=notice, including the null case for countries other than BORME/BODACC/Companies House. It omits error behavior for unknown IDs, which keeps it short of a 5.

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 sentences, front-loaded with the action and payload, followed by the prerequisite. No filler, and the conditional include behavior is stated inline rather than in a separate rambling clause.

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 no output schema, the description carries the burden of describing returns and does so well: before/after values plus the optional source publication. For a two-parameter read tool this is nearly complete; only failure/not-found behavior is unaddressed.

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 both parameters are already documented, and the description largely restates them (internal ID; include=notice attaches the publication). The added nuance is that the publication may be null outside the three named registries, which is a small increment over the schema wording.

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 ("fetch a single corporate-event record") plus the keying mechanism (Prometiam internal ID) and the payload (before/after values). It contrasts implicitly with the list-style siblings events_search and events_timeline by positioning itself as the single-record retrieval.

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 an explicit prerequisite workflow: "Get an ID from events_search or events_timeline first," which routes the agent to the correct siblings for discovery. It does not spell out a when-not case (e.g. use events_search when you have no ID), but the dependency is unambiguous.

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