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

With no annotations, the description must fully disclose behavior. It does so by listing the exact contents of the brief, suggesting a read-only operation. No side effects or destructive actions are implied. However, it does not mention rate limits, authentication needs, or what happens on invalid input, keeping it from 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?

The description is a single sentence that efficiently conveys the tool's purpose and contents. It is front-loaded with key terms ('Negotiation-ready true-cost brief'). Each listed item is relevant, and there is no fluff. Could be split into shorter sentences for clarity, but remains concise.

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 tool with one parameter and no output schema, the description adequately covers what the tool returns. It specifies the brief's components, which is sufficient for an agent to understand the output. However, it lacks information on error handling or edge cases, leaving slight room for improvement.

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 100%, so the description need not add much. The parameter 'slug' is described in the schema with examples. The description adds context ('for one product') but does not deepen understanding of the parameter beyond the schema. Baseline 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?

Clearly states the tool returns a 'negotiation-ready true-cost brief for one product' and enumerates specific contents (real renewal-rate costs, vendor transparency score, discount programs, negotiation tactics, negotiable vs fixed, and a link). The verb 'get' and resource 'cost guide' are specific, and the description distinguishes it from siblings like get_hidden_costs or get_pricing by focusing on negotiation readiness.

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 indicates usage for a single product ('for one product') but does not explicitly state when not to use or suggest alternatives. No guidance on prerequisites or when to prefer this over sibling tools like calculate_tco or get_pricing. Implied usage is clear, but explicit exclusions are absent.

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