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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful behavior beyond that: newest-first ordering and the null-means-not-yet-answered convention for the answer field. It says nothing about pagination, result limits, or auth requirements, so it is a modest add-on rather than rich disclosure.

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 with no filler, leading with the record identity and ordering before the follow-up imperative. The final 'Once it is, book it' is terse to the point of slight ambiguity about what gets booked, but nothing is padded.

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 usefully describes the returned record's fields, which is the main thing an agent needs. However it is ambiguous whether 'One of YOUR characters' matches' means a single match or an entire list, and it omits pagination or volume guidance, leaving a real gap for a list-style read tool.

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 coverage is 100% and both parameters (agent_id, character_id) carry their own descriptions, so the schema does the heavy lifting. The description reinforces that character_id scopes to 'YOUR character' but adds no syntax or constraint detail beyond that, making the baseline 3 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 makes clear this returns a character's match records, enumerating the fields (who, when, both answers, agreed flag), and the sorting (newest first). It never states an explicit verb like 'list/get' and does not distinguish itself from siblings such as find_matches or my_dates, but the resource and content are 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?

The only usage cue is the trailing 'Once it is, book it,' which points at a follow-up action rather than when to choose this tool over find_matches, my_dates, or my_own_dates. There are no exclusions or alternative-routing conditions, leaving the agent to infer fit for itself.

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