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

Annotations already cover safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=true, openWorldHint=true). The description usefully adds 'never signs or submits' – clarifying the boundary of what the tool does versus a submit step. Beyond that it adds little about idempotency semantics, retry behavior, or what the returned unsigned action contains.

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?

Two compact sentences, front-loaded with the verb and resource, followed by the non-signing constraint. No wasted text.

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 4-required-param unsigned-action tool with 0% schema coverage, no output schema, and no annotations explaining param contracts, the description leaves too much unspecified – parameter contracts and sequencing relative to siblings are missing.

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% and the four required parameters (access_token, session_id, event_signer_public, idempotency_key) carry no per-field documentation. The description mentions only event_signer_public being caller-generated; access_token, session_id, and idempotency_key remain undocumented in both schema and description, so it fails to compensate for the coverage gap.

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 (prepare) and resource (CCTP burn action) with the defining qualifier 'unsigned'. It is distinguishable from siblings like prepare_source_action and prepare_destination_action only by the 'CCTP burn' wording; no explicit contrast is drawn.

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?

Description gives no when-to-use guidance relative to the many prepare/observe siblings. It notes a precondition ('requires caller approval') but not the conditions selecting this tool over prepare_source_action or prepare_destination_action.

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