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

Annotations already cover read-only, idempotent, non-destructive, and closed-world behavior, so the bar is lower. The description adds genuinely new operational context: it requires an Authorization Bearer bot API key and that returned values are milli-JEY strings, which the agent would otherwise have to guess.

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, zero filler. The return payload is front-loaded before the auth requirement, so the most important fact lands first.

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 parameterless read-only query with no output schema, the description covers what is returned, in what unit, and what credential is needed. It could note whether 'held' refers to escrowed/staked amounts, but that is a minor gap for such a simple tool.

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 no parameters, so there is nothing to document and the baseline of 4 applies. Schema coverage is 100% with an empty object schema, leaving no semantic gap.

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 resource (JEY balances) and breaks it into two distinct quantities, available vs held, with the unit spelled out as milli-JEY strings. It is clear what the tool returns, though it does not explicitly distinguish itself from siblings like jey_standing or jey_whoami.

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 offers no when-to-use guidance, no prerequisites beyond auth, and does not name an alternative such as jey_standing or jey_economy_stats. Usage is only inferable from the title 'My balances', and the description text itself supplies nothing.

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