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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds that results carry provenance (which source said a value and when), which is useful context beyond annotations, but says nothing about ordering, result size, or what happens for a field with no recorded history.

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 tight sentences: the scope of what is returned comes first, the usage cue second, with no filler. The optional 'format' parameter and default are never touched, but that is a schema concern rather than wasted wording.

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 three-parameter, read-only lookup with no output schema, the definition covers purpose, return content, and a usage cue adequately. It stops short of describing result shape or empty-history behavior, which matters since no output schema exists to fill that 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?

The parenthetical examples (phone, hours, address, name) map to the 'field' parameter, but the schema already provides those exact examples plus the behavior for omitting the field. With 67% schema coverage, the description neither needs to nor does add meaningful semantics beyond the structured fields.

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 a specific resource and scope: the full set of values a single fact (phone, hours, address, name) has held, with source attribution and timestamps. It implicitly distinguishes itself from get_business_record by framing this as historical rather than current, but never names that sibling explicitly.

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?

"Use it when a value matters and you want to judge how settled it is" gives a genuine intent-based cue for when to reach for this tool. However, there is no when-not guidance and no explicit pointer to get_business_record for the current value, leaving the agent to infer the boundary.

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