Cost Management MCP

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions 'check' which implies a read-only operation, but doesn't specify whether this requires authentication, has rate limits, returns real-time or cached data, or what happens if the provider isn't supported beyond the enum. For a tool with no annotation coverage, this is a significant gap in transparency.

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, efficient sentence with zero waste—it directly states the tool's function without unnecessary words. It's appropriately sized for a simple tool and front-loaded with the core purpose, making it easy to parse quickly.

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 tool's low complexity (one parameter, no output schema, no annotations), the description is minimally adequate but incomplete. It covers the basic purpose but lacks details on usage context, behavioral traits, and how it fits with siblings. Without output schema or annotations, more guidance on expected returns or operational constraints would improve completeness.

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 description adds minimal meaning beyond the input schema, which has 100% coverage and fully documents the single 'provider' parameter with an enum. The description implies the tool checks balance for a provider, but doesn't elaborate on what 'balance or credits' means (e.g., monetary, API credits, usage limits). Baseline 3 is appropriate since the schema does the heavy lifting.

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's purpose with a specific verb ('check') and resource ('remaining balance or credits for a provider'), making it immediately understandable. However, it doesn't explicitly differentiate from sibling tools like 'aws_costs' or 'openai_costs', which might also relate to provider financial information but with different scopes (e.g., costs vs. balance).

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 provides no guidance on when to use this tool versus alternatives. With sibling tools like 'cost_breakdown', 'cost_trends', and provider-specific cost tools, there's no indication of whether this is for real-time balance checks, historical data, or how it differs from other financial tools. This leaves the agent guessing about appropriate contexts.

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