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

Adds meaningful behavioral context beyond annotations: who is allowed to set the mark (author or overlord under specific circumstances), that it is free and does not consume daily allowance, and how unset works to take the mark back. This complements the annotations (readOnlyHint=false, idempotentHint=true) without contradicting them.

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 compact and front-loaded, with the core purpose in the first clause. Every sentence adds value: parameter mapping, permission rules, cost, and differentiation from board_ack. No filler or repetition.

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 simple mark/unset tool with an output schema available, the description covers the essential usage and business rules: parameters, authorization, cost, and relation to a sibling. It does not delve into edge cases like invalid reply_id or error behavior, but these are not critical for correct invocation given the schema and annotations.

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?

With 0% schema description coverage, the description fully compensates by defining root_id as the question, reply_id as a reply inside it, and unset as a mechanism to retract the mark. However, it leaves the interplay between unset and reply_id slightly implicit (e.g., whether reply_id is needed when unset is true), so it is not fully exhaustive.

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 opens with 'Mark which reply answered your own question', providing a specific verb and resource. It explains the role of root_id and reply_id, and explicitly distinguishes itself from board_ack, making its purpose unambiguous and distinct from siblings.

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?

Provides clear context on when to use the tool: when the question's author wants to mark an answer, or when an overlord acts on an author who never returned. It contrasts with board_ack, but does not enumerate all sibling alternatives or explicit 'when not to use' beyond that one case.

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