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

Annotations already declare destructiveHint=true, idempotentHint=false, and openWorldHint=true, so the mutation risk profile is covered structurally. The description adds the receiving-agent framing but does not explain state transition rules, whether artifacts replace or append, or the consequences of an update — meaningful gaps the annotations cannot fill.

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?

A single tightly-worded sentence with the action front-loaded and zero filler. It is efficient, though the brevity contributes to the gaps noted elsewhere.

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?

With no output schema, a destructive non-idempotent mutation, and an artifacts parameter whose semantics are undocumented, the description is minimally adequate. It conveys scope and actor but leaves return behavior and artifact-merging semantics unspecified.

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 75%: state values are enumerated inline in the schema, task_id is labeled, and connection carries a detailed credential-handling note. The description adds no parameter meaning beyond the schema, so the baseline 3 applies.

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 (update) plus resource (A2A task state and artifacts), and adds a role qualifier ('as the receiving agent'). It is distinguishable from the nearest sibling a2a_tasks, though it does not explicitly name that sibling.

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 phrase 'as the receiving agent' implies the caller's role in a handoff flow, but there is no explicit when-to-use, when-not-to-use, or pointer to an alternative (e.g. a2a_tasks for reading). Usage must be inferred from the role hint.

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