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

Annotations already cover read-only, idempotent, and non-destructive behavior, and the description adds genuinely useful context beyond those: the 0.004 USDC cost, determinism, evidence-boundedness, and signed output. It does not detail what the fee pays for or how the 'evidence-bounded' guarantee manifests, but it complements the annotation profile rather than merely repeating it.

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 short fragments each carry distinct information: the core action, the cost, and the tool's guarantees. The description is front-loaded and every phrase earns its place, though the mixed semicolon/period punctuation is slightly awkward.

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 tool with an open input schema and several close siblings, the description leaves meaningful gaps: what '0.004 USDC' refers to (fee vs bound amount), what the required input properties are, what 'evidence-bounded' means operationally, and when to prefer this over mcp_a2a_task_bridge. The existence of an output schema covers return values, but the input and selection contract is incomplete.

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 zero named parameters, the schema provides no constraints, and a 0-param baseline of 4 would normally apply. But the schema is an open object with minProperties 1, so the agent must guess which properties to supply. The description hints at relevant entities (A2A task, transaction, USDC, authority) but never maps them to concrete input fields, leaving the input contract underspecified.

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 states a specific verb and resource ('Bind an A2A task to a transaction') plus a key constraint ('without silently transferring authority'), which gives the agent a clear action and a distinguishing negative. It does not, however, explain the 'A2A' jargon or differentiate itself from the close sibling mcp_a2a_task_bridge, so it falls just short of a 5.

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 'without silently transferring authority' implies a usage condition: use this when you want to associate a task with a transaction but not hand over authority. However, the description never names alternatives or states when not to use the tool, and the sibling list contains several overlapping bridges (mcp_a2a_task_bridge, ap2_mandate_bridge) that are left unaddressed.

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