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

No annotations are provided, so the description carries the full burden. It identifies the tool as a mutating operation but does not disclose side effects, state-transition rules, ownership/permission requirements, whether artifacts are merged or replaced, or what the response contains. This is a significant gap for a task-state mutation tool.

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 a single, front-loaded sentence that names the action, target, and affected fields without filler. It is concise and easy to parse, though it omits useful behavioral context that would strengthen the definition.

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 state-changing tool with no annotations, no output schema, and a sensitive connection parameter, the description is too thin. It does not explain state-transition implications, pruning/merging of artifacts, authorization expectations, or when the connection parameter is required. An agent would likely need to inspect other sources before invoking this reliably.

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 high (75%), with the state parameter listing its allowed values and connection explaining its source and privacy requirement. The description adds little parameter meaning beyond the schema, and 'artifacts' remains poorly specified, so the baseline score of 3 is appropriate.

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 uses a clear verb ('Update') and resource ('A2A task state and artifacts'), and adds the role context 'as the receiving agent.' It is specific enough to identify the operation, though it does not explicitly distinguish itself from siblings like a2a_tasks or task_context_update.

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 gives no guidance about when to use this tool versus alternatives, nor any exclusions or prerequisites. The 'as the receiving agent' phrase hints at context, but there is no explicit statement of when this update path is appropriate or when another task-related tool should be used.

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