GCP Billing and Monitoring MCP Server

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 'detailed cost analysis with trends and insights', which implies a read-only operation, but doesn't specify permissions required, rate limits, output format, or whether it's a heavy/computational query. For a tool with 6 parameters and no annotations, this is insufficient to inform safe and effective usage.

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 that front-loads the core purpose without unnecessary words. It directly states the action and scope, making it easy to parse quickly. Every part of the sentence contributes to understanding the tool's function.

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 complexity (6 parameters, no annotations, no output schema), the description is incomplete. It lacks details on behavioral traits (e.g., permissions, rate limits), usage context relative to siblings, and expected output format. While the schema covers parameters well, the overall guidance is too sparse for effective agent operation in a crowded toolset.

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 no parameter-specific information beyond what's in the input schema, which has 100% coverage with detailed descriptions for all 6 parameters. This meets the baseline of 3, as the schema adequately documents parameters like 'billingAccountName', date ranges, filters, and 'groupBy' with its enum. No extra value is provided in the description.

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 as 'Perform detailed cost analysis with trends and insights for Google Cloud billing data', which includes a specific verb ('analyse') and resource ('billing data'). It distinguishes itself from siblings like 'gcp-billing-detect-anomalies' or 'gcp-billing-service-breakdown' by emphasizing 'trends and insights', but doesn't explicitly contrast with them, preventing a perfect score.

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 siblings like 'gcp-billing-service-breakdown' or 'gcp-billing-cost-recommendations', there's no indication of context, prerequisites, or exclusions. This leaves the agent without direction on tool selection, relying solely on naming conventions.

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