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

Beyond readOnlyHint=true, the description discloses conditional return behavior: version_count, source_count, first_edition_seen and last_edition_seen appear only when a record holds multiple forms/sources, and older-edition records are flagged. This is genuine behavioral context the annotations do not cover, though it never clarifies what a 'form' or the 'Union' actually are.

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?

The core purpose is front-loaded, but the remaining text is dense, jargon-heavy and hard to parse ('never the record's whole span', 'reads exactly as it always has'), and spends sentences on backwards-compatibility meta-commentary that adds little for an agent. It is over-long for a one-parameter read tool.

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 must carry return-value meaning, and it does describe fields and conditional presence. However, key terms ('form', 'Union', 'source') are never defined, leaving an agent without a clear mental model of what is actually returned.

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?

With a single parameter and 100% schema description coverage, the schema already documents policy_id as 'A policy id from find_policies.' The description adds nothing further about the parameter, so the baseline of 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 opening sentence gives a specific verb and resource with the returned fields (section, verbatim text, page, edition, source) and distinguishes itself from list tools ('come from the one-record get, never from a list'). It is clear this retrieves a single policy, though the sibling differentiation is partial rather than explicit.

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 schema ties policy_id to find_policies, and the description notes forms 'come from the one-record get, never from a list.' There is no explicit statement of when to call this versus find_policies or get_catalog, so the guidance remains inferential.

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