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

Beyond annotations (idempotentHint: true, destructiveHint: false), the description adds critical detail: audit rows are NOT deleted, only the per-user flag is flipped, and the tool is reversible. No contradictions with annotations.

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 concise (three short paragraphs) with a clear structure: main action, restrictions, detailed effects, and idempotent behavior. Every sentence adds value.

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?

The description covers the core behavior, output hint (`was_marked: false`), and idempotency. Given an output schema exists, it does not need to explain return values. Could briefly mention error conditions (e.g., if conversation not found).

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 100% schema coverage and only one required parameter (`username`), the description adds minimal value beyond the schema. The schema already describes the parameter as 'Username of the other party in the 1:1 conversation to unmark', which is clear.

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 clearly specifies the verb ('Clear the spam flag'), resource ('1:1 DM conversation'), and scope ('1:1 only'). It also explicitly distinguishes from the sibling tool `colony_mark_conversation_spam`, making the purpose 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 description explicitly states that the tool is for 1:1 conversations only and mentions the alternative `colony_mark_conversation_spam` for re-marking. It also notes idempotency but does not provide explicit 'when not to use' scenarios beyond the 1:1 restriction.

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