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

With no annotations provided, the description carries the full behavioral burden, and it delivers: 'Stable task ID + revision prevents overwrite' discloses concurrency semantics, 'never auto-completes this task' clarifies side effects, and 'completed dependency emits a resume suggestion' explains async behavior. It also flags a provider processing precondition that is absent from the schema.

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 four dense sentences with no filler. The main action is front-loaded, and every subsequent sentence introduces a distinct behavioral or privacy consideration: host invisibility, overwrite prevention, dependency behavior, and provider opt-in.

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 9-parameter tool with no annotations and no output schema, the description covers a lot: purpose, concurrency, async side effects, and privacy/auth context. It stops short of 5 because 'provider processing requires private opt-in' remains vague, and there is no explanation of what happens on revision mismatch or what the tool returns.

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 high at 78%, giving the baseline of 3. The description adds value by explaining that 'Stable task ID + revision prevents overwrite,' which gives meaning to the revision and task_id parameters. It also clarifies that the objective is an explicit goal or blocker, reinforcing the schema's minimal 'Goal or blocker' description.

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 starts with a specific verb and resource: 'Save an explicit private local goal or blocker.' It also adds a distinctive scope marker with 'Tincan cannot see host work,' which helps separate this private, local task context from public or agent-to-agent task tools. However, it does not explicitly name or differentiate any sibling tool such as a2a_task_update, so differentiation is implied rather than stated.

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 clearly implies when to use the tool: for saving private local goals or blockers that host-side systems cannot see. It also hints at preconditions like 'Provider processing requires private opt-in.' Still, it does not explicitly contrast with alternatives, mention when not to use it, or name a preferred sibling for other cases.

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