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

Annotations already declare readOnlyHint=true, so safety is covered. The description goes further by naming the fields surfaced and noting that partner accounts are included alongside staff, which is real behavioral context absent from the annotations.

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 short sentences: the first front-loads what is listed and what comes back, the second gives the downstream-consumption note and the backing endpoint. No filler.

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?

With no output schema, the description compensates by enumerating the returned fields, and with no parameters there is nothing else to document. It also cites the underlying API endpoint for traceability, leaving no material gap.

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 tool takes zero parameters, so the baseline is 4. The description adds a semantic link by explaining that the returned account_id is the value consumed by CHECKFRONT_ON_BEHALF, tying the output to downstream use.

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 precise verb+resource ('List the staff (and partner) accounts on the Checkfront account') and enumerates the returned fields (ids, names, emails, login ids, enabled flag). No sibling tool lists staff accounts, so an agent can distinguish it immediately.

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 supplies a concrete usage hook: 'The account_id is what CHECKFRONT_ON_BEHALF takes,' telling the agent why it would call this tool. It does not state exclusions or alternatives, but no sibling overlaps this capability.

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