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 only the word 'live', hinting the read is a fresh real-time fetch rather than cached data; there is no mention of auth requirements, rate limits, or error behavior for a missing account.

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 compact sentences with no redundancy. The purpose and returned fields are front-loaded, with the endpoint path as a trailing technical detail.

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?

There is no output schema, and the description helpfully enumerates the return contents (plan, credits, tokens remaining), which is what an agent needs to know before calling. What remains unspecified — behavior when the email is unknown, and how this differs from flowmusic_get_usage — is minor for a simple single-resource read.

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 100% and the single email parameter is already documented as 'The account email.' The endpoint template GET /accounts/{email} reinforces that email is the lookup key, but adds no format or validation detail beyond the schema. Baseline 3 applies.

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 and resource ('Read one account live from Flow Music') and enumerates the returned data (plan, credits and tokens remaining), plus the underlying GET /accounts/{email}. The singular 'one account' implicitly distinguishes it from the sibling flowmusic_list_accounts, but it never names that sibling 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?

Usage is only implied: 'one account' suggests this is for looking up a single known email rather than enumerating accounts or usage statistics. No explicit when-to-use, prerequisites, or routing to flowmusic_get_usage / flowmusic_list_accounts is provided.

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