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. The description adds genuinely useful charging context ('Completed lookups cost at least 10 Nexscope credits', 'Repeated requests may purchase data again'), but it contradicts itself by also stating '1 credit per request', which leaves the actual cost ambiguous.

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 text reads like scraped marketing copy: the purpose sentence appears twice, pricing appears twice with conflicting figures, and fragments such as 'API View Pricing' and 'Examples are not guaranteed prices' add no invocation value. The one useful fact (10+ credits, repeat calls may re-purchase) is buried in boilerplate.

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 should say what an event record contains (dates, venue, hosts, ticket info), but it says nothing. It also fails to resolve the practical ambiguity that neither id nor url is required, leaving an agent without guidance on what a valid call looks like.

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% and both parameters are documented there, so the baseline is 3. The description adds only that either a URL or an id identifies the event, without clarifying whether one is mandatory (the schema shows no required fields), whether both may be supplied, or how the two interact.

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 opening sentence, 'Get a specific event by its URL or id', names a concrete verb, resource, and the two accepted identifiers, so an agent knows exactly what the tool retrieves. It does not differentiate itself from siblings such as social_facebook_events, social_facebook_events_search, or social_facebook_profile_events, and the purpose statement is repeated verbatim mid-description, but the core purpose 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 only implied: the mention of 'URL or id' suggests this is the lookup to use when the caller already holds an identifier rather than search terms. There is no explicit statement of when to prefer it over social_facebook_events_search or social_facebook_profile_events, and no prerequisites or exclusions are given.

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