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

The description adds critical behavioral context not covered by annotations, including pricing ($0.01/call, credit usage, free initial calls), the fact that it is read-only/computational and non-mutating, and charging per call.

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 description is highly dense and efficient, packing operational constraints (pricing, free calls, charging per call) alongside technical function in a well-organized format.

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?

Given the complexity of a multi-feature block retrieval tool (including cost, error handling, and data types), the description is extremely comprehensive. It provides all necessary context for safe and correct invocation.

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?

While the schema covers the structure, the description adds crucial semantic meaning to the 'number' parameter by specifying that it accepts either a decimal block number or the string 'latest' for default behavior.

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 states the tool retrieves 'Latest block number and block details on Sonic' or details for 'any block by decimal number.' It effectively uses context and mentions siblings to differentiate its scope (Sonic chain).

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?

It provides explicit usage guidance by directing users to 'sonic_gas' for current fees, and informs the agent about the specific input formats (latest vs. decimal number). It also clearly defines the expected result for missing blocks (404).

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