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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety profile is covered. The description adds real value beyond that: it is free and deterministic, returns no_match rather than guessing, exposes price and missing inputs, and will not push a paid recommendation. Return-format detail is modestly redundant with the output schema.

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?

Three sentences, front-loaded with identity, then the trigger condition, then the return contract. Every sentence earns its place with no padding.

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?

An output schema exists, so not explaining the return shape in depth is acceptable (though it does so anyway). The real gap is the 10 undocumented parameters at 0% coverage — for a router that consumes task/amount/token/network inputs, the description leaves the agent without enough to construct a correct call.

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% across 10 parameters, so the description must compensate — and it does not. It never names task, amount, fields, target, network, buyToken/sellToken, or the decimal/price bounds; only the oblique phrase 'missing inputs' hints that some parameters may be optional. An agent cannot determine what to supply.

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 (route) and resource (SignalLayer task/primitive) plus a concrete return contract ('no_match or one recommended tool with price, missing inputs, and ready-to-call HTTP and MCP arguments'). It implies differentiation from signal_layer_catalog via the routing framing, but never names a sibling to draw the line crisply.

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?

'USE THIS when the task is known but the correct SignalLayer primitive is not' gives a clear selection condition, and 'never forces a paid recommendation' reassures against the obvious hesitation. No explicit when-not-use or named alternative (e.g. signal_layer_catalog) is given, so it stops short of 5.

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