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

Annotations already carry the safety profile (readOnly, idempotent, non-destructive, openWorld), so the bar is lower, yet the description adds real context beyond them: it checks current withholding and source rules, and explicitly states it does NOT refresh the museum observation timestamp. That non-refresh guarantee is exactly the kind of behavioral trait an agent cannot get from the annotations.

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 short sentences, zero filler. The core action is front-loaded and the second sentence is a genuinely distinct constraint rather than padding. Every sentence earns its place.

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 carries more of the burden, and it does signal that the response reflects current withholding and source rules. It stops short of describing the shape of the returned record or error behavior for a stale/invalid ref, but for a simple read-only getter it is close to complete.

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 the single nested ref object is well documented in the schema itself (including "Never invent identifiers"), which sets the baseline at 3. The description adds nothing about the ref structure, identifier provenance, or which fields are the stable key, so it does not exceed the schema.

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 gives a specific verb and resource ("Retrieve a previously observed museum record from Finder") and the word "previously observed" signals this is a read of an existing record rather than a fresh lookup. It does not name or contrast with the closest siblings (still_resolve_artwork, still_search_open_art), so an agent must infer the boundary. Clear purpose, no explicit sibling differentiation.

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?

"a previously observed museum record" implies the record must already exist and be identified by a ref, which is usage context, but the description never states when to choose this over still_resolve_artwork or still_search_open_art. No prerequisites, no exclusions, no alternatives are given. Usage is only implied.

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