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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds the key behavioral detail that 'resolved' is false when the input did not become an arXiv id, which is important for agents to know how to interpret the result.

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 sentences with no wasted words. The core purpose is front-loaded, and the failure-mode note ('resolved' is false) is a valuable addition that 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?

For a single-parameter, read-only, idempotent tool with a full schema and output schema, the description is nearly complete. It could explicitly state that the output is the arXiv id string, but the phrase 'into the arXiv id' plus the output schema covers this. The failure-mode disclosure is the most valuable contextual addition.

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%, so the schema already documents the 'reference' parameter thoroughly. The description adds a small amount of context by listing the accepted formats, but this largely mirrors the schema's parameter description. Baseline 3 is appropriate.

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 verb ('Turn') and resource ('a pasted arXiv id, arXiv URL, DOI, or Pith Number') and clearly defines the output ('the arXiv id the other tools key on'). It distinguishes itself from siblings by explaining that this is the normalization step for other tools.

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?

The description implies when to use this tool: when you have a reference in one of the listed formats and need the canonical arXiv id. It doesn't explicitly name alternatives or exclusions, but the sibling list shows other paper-related tools, and the description's 'the other tools key on' makes the routing clear.

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