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

Annotations already declare readOnly/idempotent/non-destructive, so safety is covered. The description adds genuinely useful behavioral context beyond that: only public gatherings are returned, and gatherings with private addresses are withheld from city listings entirely, plus it promises honesty when nothing is listed.

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 core scope statement is front-loaded and clear, but the middle section is padded with quoted user queries and a rhetorical closing ("with the door to every gathering") that adds tone rather than information. Efficient enough but not tight.

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 an output schema present and rich annotations, the description needn't explain return values, and it covers scope, privacy filtering, and empty-result behavior. What remains missing is explicit routing against the near-identical sibling find_gatherings_near.

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 city, hours, and country are already documented with types, ranges, and defaults. The description only restates the 12-hour default, adding no syntax or semantics beyond the schema. Baseline 3 applies.

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+resource+scope: public Christian gatherings starting in the next 12 hours in a given city, with concrete event types enumerated. It does not, however, name or distinguish itself from the close sibling find_gatherings_near or events_this_week, so the agent must infer the boundary.

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 embedded example queries ("is there a prayer meeting tonight in Atlanta", "Bible study tonight near me") give clear usage context for the tonight-window case. No explicit when-not or alternative-tool routing is given, so it falls short of a 5.

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