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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so safety is covered. The description adds two pieces of real context beyond them — that it is free and that estimates remain separate from observations — but says nothing about pagination, ordering, or the default window covered by the report.

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?

It is short and has no filler, but it is a fragmented noun-phrase list rather than a front-loaded statement of action and purpose, so the agent's first read does not answer 'what does this do?'

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?

An output schema exists, so return values needn't be described, and annotations cover the safety profile. Still missing for a correct call: the meaning of `limit`, the reporting window, and when this report is the right choice over sibling ledger/state tools.

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 0% for the single `limit` parameter, and the description never mentions it. It does not say whether limit bounds records, rows, or report sections, so the description fails to compensate for the undocumented parameter.

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 is a column list ('decision/outcome receipts, route modes, compute avoided, predicted savings, ...') rather than a verb+resource statement, so the agent must infer that this tool returns/reports those metrics. It is distinguishable from siblings like get_ledger only by the specific metric vocabulary, not by an explicit statement of what is produced.

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?

There is no guidance on when to call this versus get_ledger, export_state, or record_route_outcome, nor any mention of prerequisites. The only usage-adjacent signal is the phrase 'Free read', which hints at cost but not selection criteria.

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