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

With no annotations, the description carries the full burden. It does disclose the returned content (limits, remaining, stopped reason, ledger tail) and one operational rule about close=true, which is real behavioral value. However, it never explains what actually happens when close=true (does it finalize/destroy the budget, is it reversible?), nor any auth or side-effect profile, which are the key unknowns for a tool with a mutating flag.

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 dense sentences with zero filler. The status/inspection content is front-loaded and the conditional instruction is placed last where it belongs.

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, so the description usefully enumerates what the caller gets back, and it flags the one required handle. The remaining gap is the semantics of the close parameter, whose consequence is never stated — a notable omission for a tool that may terminate a budget.

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 coverage is only 50%: handle is well documented in the schema itself, but close has no schema description. The description partially compensates by stating the condition for close=true, yet it leaves the flag's effect unspecified. This is a marginal improvement over the schema, not full coverage.

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 gives a specific read verb plus a concrete resource enumeration: spend vs limits, remaining budget, run-stopped status and reason, and the last 20 ledger events. An agent can tell this apart from budget_record, budget_reserve, or budget_open_budget by the read-only status framing, though it never explicitly names those siblings.

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?

It provides one conditional usage hint ('Set close=true when the run finishes') that tells the agent when to use a flag. Beyond that there is no guidance on when to call this versus budget_usage_and_upgrade, budget_weekly_report, or budget_record, and no stated prerequisites apart from the handle.

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