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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is fully covered by structured data. The description adds a sense of what the record aggregates (multiple ban lists plus Steam VAC data), but since an output schema exists, most of that return detail is redundant; it says nothing about rate limits, lookup failures, or behavior for unknown players.

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 tight sentences, front-loaded with the outcome rather than the mechanics, with zero filler. The second sentence partially overlaps the `query` schema description, which is the only minor redundancy.

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?

For a single-parameter read-only lookup with a full output schema, the description covers purpose, input forms and record contents adequately. The only real gap is absence of routing guidance relative to the sibling lookup/list tools, which matters given check_players sits next to it.

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%, so baseline would be 3, but the description meaningfully expands the accepted input space beyond the schema's generic "player id, profile link or name": SteamID in any form, Steam profile link, Discord id, or Minecraft name. That is genuine semantic value an agent would not infer from the schema alone.

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 states a specific verb and resource ("Look up a player's Mizan record") and enumerates what the record contains: bans across every list, cheating flags, and Steam VAC/game bans. This is far more specific than the title alone, though it never names the sibling check_players or explains how single-player lookup differs from it.

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 second sentence gives strong guidance on what inputs are accepted, but there is no explicit when-to-use / when-not-to-use framing and no mention of when to prefer check_players or list_sources instead. Usage is implied by the scope of what is returned rather than stated.

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