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

With no annotations, the description carries the full burden and does disclose real behavioral traits: free engines require no key, paid engines authenticate via the Authorization header, and running a paid engine spends credits. It omits failure/error behavior, idempotency, and rate limits, keeping it below 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?

Two tight sentences with the core action front-loaded and the auth/billing caveat immediately after. No filler.

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?

Covers purpose, auth, and cost, but with no output schema and no annotations the agent gets no information about return values or error conditions for a tool with a nested object input. Adequate but with clear gaps.

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% (engine_id is undocumented) and the description adds nothing about how to obtain engine_id or what shape 'structured input' takes. It does reference the inputSchema contract indirectly, but an agent still needs get_engine to call this correctly.

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 (run) and resource (decision engine) plus the input shape (structured input), so an agent can distinguish it from get_engine/list_engines. It does not differentiate itself from the potentially overlapping sibling evaluate_fit, so it falls short of a 5.

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?

Usage is only implicit: run an engine when you have an engine_id and matching input. The free-vs-paid distinction hints at prerequisites but names no alternative tool or exclusion, and never says when to prefer this over evaluate_fit.

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