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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered. The description adds return-content context: the exact currency set, the creator minimum floor per currency, and an `echanges` swaps field built by `tblock_plan_swap`, which is valuable because there is no output schema. It repeats 'Read-only, no input' and omits pagination/auth details, keeping it from a 5.

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 front-loaded sentence beginning with the verb and primary resource. The parenthetical currency list and `echanges` clause are dense but informative, though the sentence is somewhat run-on.

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, the description must carry return-value information, and it does name the currencies, creator minimums, and an `echanges` swaps field. It still lacks output structure or pagination details, but for a zero-param read-only reference tool it is reasonably complete.

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?

The tool has zero parameters, so the baseline is 4. The description's 'no input' is consistent with the empty schema and requires no further parameter explanation.

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 ('Lists') and resource ('currencies a new block can be paired with at birth on TokenizedBlock'), enumerates the currencies, and names the related `tblock_plan_swap` builder. An agent can tell this is a reference/list tool rather than a plan-building or panel-state tool.

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?

No explicit when-to-use or when-not-to-use guidance. The description says it is read-only and takes no input, but that is not usage routing; it does not tell the agent when to choose this over `tblock_creator_minimum` or `tblock_plan_swap`.

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