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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is fully covered. The description adds the useful nuance that the returned limits are 'plan-aware', but it says nothing about auth requirements, rate limits, or how the optional time/workspace scoping changes results.

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?

A single tight sentence with no filler and the resource front-loaded. It is appropriately sized, though it is so brief that it leaves obvious questions (time range, filtering) unaddressed.

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 read-only metrics endpoint with no output schema, the description conveys the essential purpose and that it returns both usage metrics and plan-aware limits. However, with 5 parameters at 40% coverage and an undocumented nested 'query' object, the definition does not explain how the optional filters shape the response.

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 only 40%; only workspace_id (and the generic 'query' override) are documented, while to, from, and brand_id carry no explanation in either schema or description. The description mentions zero parameters, so it does not compensate for the coverage gap and leaves the filtering semantics of the time range and brand ambiguous.

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 states a specific verb ('Get') and resources ('usage metrics and current plan-aware limits') scoped to 'the API key'. This is clear and distinguishes it from a pure balance check like get_ai_credit_balance by emphasizing plan-aware limits, though it never names a sibling tool explicitly.

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?

There is no guidance on when to use this tool versus alternatives such as aidelly_get_ai_credit_balance, aidelly_get_agency_overview, or the analytics-summary tools. No preconditions, exclusions, or routing cues are given, so the agent must infer usage entirely.

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