polygon_block

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

With no annotations provided, the description bears the behavioral burden; it does disclose a notable behavior by stating 'Pay-per-call ($0.005 USDC)' and it lists the fields that will be returned. However, it does not state read-only semantics, default behavior when no block number is supplied, response structure, or error/rate-limit behavior, leaving relevant behavioral gaps.

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 entire definition is one tight, front-loaded sentence. It starts with the core purpose, specifies the key selection mechanism, enumerates the returned data, and appends the pricing detail without wasted words.

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 no output schema and no annotations, the description should be self-sufficient, but it omits crucial invocation details: the meaning of 'fields', whether 'number' has a default when omitted (required list is empty), and what the full response shape is. The listed output fields help, but an agent could still call the tool incorrectly.

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 coverage is only 50%, and the description adds little beyond what the schema already says. It repeats that a block can be addressed by number or 'latest', which the schema documents, but it never explains the 'fields' parameter, its accepted format, or how the listed output fields relate to it.

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 clearly identifies the resource (a Polygon block), the lookup key (number or 'latest'), and the returned contents (hash, timestamp, tx count, gas used, base fee), which distinguishes it from chain-specific siblings like base_block. It lacks an explicit verb such as 'fetch' or 'get', so it falls just short of the strongest purpose statement.

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 choose this tool over alternatives, nor does it mention any exclusions or fallback tools. It is inferable from the name and the phrase 'polygon block' that this is for block header data, but the decision context is left unstated.

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