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

Annotations already mark the tool as read-only and open-world, covering the safety profile. The description adds useful behavioral context by explaining the output is normalized to 'what a simple transfer costs right now' and listing the chain-specific fee units (gwei, sat/vB, lamports, gas price). This goes beyond what the annotations alone convey.

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?

One compact sentence conveys the resource, the normalization semantics, and the relevant units without redundancy. The title and description complement each other, and every part of the description earns its place.

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 simple one-parameter read-only tool with no output schema, the description provides enough detail about what the agent can expect: current fees normalized to a transfer cost plus chain-specific knobs. It could be more explicit about the exact return format, but the tool's simplicity makes this gap minor.

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 single parameter 'chain' is fully documented in the schema as 'Chain id or alias', so schema coverage is 100%. The description repeats the chain context but does not add material detail beyond what the schema already provides. A baseline score of 3 is appropriate.

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: current fee conditions for a given chain, normalized to a simple transfer cost and expressed in chain-specific units. The title supplies the verb 'Estimate', so the tool's purpose is unmistakable. It does not explicitly differentiate itself from siblings, but 'fees' is distinct enough among the listed singularityagent__ tools.

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 clear context for when to use this tool: whenever current fee conditions on a chain are needed. It does not mention alternatives or exclusions, but the scope is specific enough that an agent can infer the appropriate call scenario.

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