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

With no annotations provided, the description carries the full burden. It discloses access requirements ('open to any active DCer who can see the event,' target must hold a valid ticket) and error condition (404 if no agenda). It does not cover auth details or rate limits, but for a simple GET endpoint, it provides sufficient behavioral context.

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 concise and well-structured: first line states the endpoint, second paragraph explains purpose and return value, third paragraph covers access conditions. Every sentence adds value, and the information is front-loaded. No unnecessary fluff.

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?

Despite lacking an output schema, the description fully explains what the tool returns ('sessions they bookmarked + meetups they RSVPd to'). It also covers access conditions and error handling. For a simple two-parameter tool, this is complete and sufficient for an AI agent to understand its usage.

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?

The input schema already covers both parameters (eventID, userID) with descriptions. The description adds minimal extra meaning—it clarifies that userID is the 'target attendee' and implies both are path parameters. With 100% schema description coverage, the description is not needed to explain parameters, so score 3 is appropriate.

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 clearly states the tool fetches another attendee's personal agenda for an event, specifying the endpoint pattern and what it returns (bookmarked sessions and RSVP'd meetups). It distinguishes from siblings like event_agenda (own agenda) and event_agendas (multiple agendas) by explicitly mentioning 'another attendee's agenda.'

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 provides explicit guidance on when to use this tool: 'Use this so an AI agent can plan together with another DCer (find a coffee window, suggest sessions to overlap, propose a meetup).' It does not explicitly list alternatives or when not to use, but the context is clear enough.

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