mark_done

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

There are no annotations, so the description carries the behavioral burden. It communicates that this is a finalization action for completed work and that note is optional, but it does not disclose whether closing is irreversible, requires permissions, or what side effects occur on the thread state. Sibling contrast with pause_thread implies terminality without making consequences explicit.

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?

Three concise sentences, each earning its place: the core action, the usage conditions with named alternatives, and the optional parameter note. Front-loaded with the primary action before routing details.

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 two-parameter finalizer, the description covers when to call, what precondition must be met, alternatives, and parameter note semantics. Missing explicit behavioral consequences like reversibility are a small gap, but the output schema exists and operation scope is simple enough that the definition is largely complete.

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 0%, so the description must compensate. It adds that thread_id must be 'known' and that note is an 'optional completion note, but it does not add meaningful constraints like where thread_id comes from or how note is stored. Coverage is minimal but minimally adequate for two simple parameters.

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 ('Close') and resource ('a specific thread') plus the completion condition ('when its finishable outcome is complete'). It distinguishes itself from pause_thread and dismiss_thread by naming them as different intent paths, so an agent can tell this tool apart 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?

Gives explicit guidance on when to use this tool and when not to, including named alternatives and their conditions: pause_thread for unfinished work and dismiss_thread for intentional abandonment. This is model-level routing guidance that goes beyond the schema.

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