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

Annotations cover safety (readOnly, idempotent, closed-world), and the description goes well beyond them: it defines what `disputed` and `dispute_reason` mean, guarantees the lists are complete for the record's watch window and say nothing outside it, and explicitly states that `applies_from: unknown` means non-deterministic parsing rather than no date. metadata_only_units/instruction_only_units semantics and a machine-computed legal disclaimer round out the disclosure.

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 front-loaded with what the record contains, but the single dense paragraph mixes output-field definitions, completeness guarantees, and a legal disclaimer, with heavy inline backtick terminology. Each clause carries some information, yet the block is longer and harder to scan than the two-parameter lookup requires.

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-value structure need not be re-explained, yet the description usefully clarifies field semantics (disputed, dispute_reason, applies_from, *_only_units) and scoping. It omits any prerequisite that act/version come from list_acts, which is the remaining 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?

Schema description coverage is 100% and both parameters are documented in the schema (act key/corpus-key, version or entry key). The description adds no format or lookup guidance beyond that, so the baseline 3 applies.

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 states what the tool returns with substance: one event of one act, with its counts, repairs, corroboration signals, and every row. That is far more specific than a restatement of the name. It stops short of naming a sibling (e.g. get_change) to disambiguate 'event' vs 'change', which is the only thing keeping it from a 5.

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: the required act+version pair signals a single-record lookup, and the sibling list includes get_change/changes_since that are never mentioned. There is no explicit when-to-use or when-not-to-use statement, so the agent must infer routing from the description's substance.

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