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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so the safety profile is handled. The description adds substantial behavioral context beyond that: token expiry with bounded automatic recovery, case_history semantics and overturn detection, and a post-answer verification step. It falls short of 5 because the return payload (citation_text, case_history, text_excerpt/truncation flags) is described only by reference, with no output schema to anchor those field names.

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?

Long but densely operational and front-loaded with the core purpose in the first sentence; the paging ritual, failure protocol, and citation-matching rule each prevent a distinct class of error. The offset guidance duplicates the schema's own description, but that redundancy is defensive rather than wasteful.

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?

With no output schema and a nontrivial pagination protocol, the description carries almost the full burden and covers truncation, contiguity proof, and the 'no advancing offset' failure case. The remaining gap is the enumerated response fields themselves, which are referenced but not itemized.

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 33% (doc_id and result_token are bare strings), so the description must compensate and does: it says both come from the search result, that tokens must be copied verbatim and never reconstructed, and it fully specifies excerpt_offset semantics (source Unicode code points, not UTF-8 bytes, use next_excerpt_offset rather than len(text_excerpt)). That is far more than the schema conveys.

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?

States a specific verb and resource ('Retrieve the full reasoning text of a judgment') and scopes it to a judgment selected from search results, which cleanly separates it from search_judgments. An agent knows immediately that this is the follow-up fetch, not another search.

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?

Explicitly names when the tool is REQUIRED ('whenever you intend to quote or paraphrase a court's holding — the search listing alone does not contain reasoning text'). It also covers recovery branches: rerun search ONCE on result_token_invalid_or_expired, never retry the same failed token, stop if recovery fails, and 'This is not a login error.'

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