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

Annotations already declare this a safe, idempotent, closed-world read, so the description needn't restate safety. It does add useful context that no output schema covers: each tour comes back with a short description and is keyed by personality archetype. It omits ordering, count, or whether results are stable — minor gaps for a simple static listing.

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?

A single sentence with zero filler, front-loaded with the action and resource before the detail. Nothing could be removed without losing information.

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 parameters and no output schema, the description carries moderate weight and does tell the agent what comes back (tours grouped/labeled by personality, each with a description). It could be fuller by pointing to start_tour as the follow-up action, but for a trivial zero-arg listing tool it is nearly complete.

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 tool takes zero parameters, so the baseline of 4 applies. The personality values in the description are output categories, not inputs, and are correctly presented as such.

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 uses a specific verb and resource ("List the guided tours") and enumerates the exact categories returned (scientist, poet, historian, detective, wanderer, speedrunner), so an agent immediately knows this is a catalog lookup, not a tour start. It does not explicitly distinguish itself from the sibling start_tour, which is the main thing keeping it below a 5.

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: an agent can infer this is the discovery step before start_tour, but the description never says when to call it versus start_tour or whether it is a required prerequisite. No exclusions or alternatives are named.

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