budget_status

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

readOnlyHint=true already tells the agent this is a safe read with no side effects, so the description only needs to add context — and it does, stating the temporal scope (today) and the unit convention (integer cents). It stops short of explaining what an "insolvency status" value looks like or whether quota/pool figures are combined or per-pool.

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, with the resource list front-loaded and the unit convention placed as a trailing caveat. Nothing here could be cut without losing information.

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 parameters, no output schema, and only a readOnly annotation, the description carries most of the burden and does cover what the call reports plus the money unit. It falls slightly short by not indicating the shape of the response (e.g. flat fields vs. per-pool entries) for the listed values.

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 per the baseline there is nothing for the description to disambiguate. The added note that money is returned in integer cents is a useful unit hint even though it concerns output rather than input.

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?

Names a specific verb (Read) and a concrete set of resources (today's quota, pool balances, overspend, insolvency status), so the agent knows this is a current-snapshot report rather than a mutation. It never explicitly distinguishes itself from the near-named sibling budget_summary, which is the main ambiguity an agent faces here.

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 by the word "today's", which suggests a current-day snapshot versus the historical data in budget_transactions or budget_summary. There is no explicit when-to-use, when-not-to-use, or named alternative, so the agent must infer the routing from sibling names alone.

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