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

The readOnlyHint annotation already signals safety; the description adds deterministic behavior and the exact fields the list will contain, which is useful context. There is no contradiction and no hidden mutation risk.

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, purposeful sentences with no filler. The core content is front-loaded and the pointer to canon_describe_formula is placed second, making the definition easy to scan.

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 parameterless read-only list, the description provides enough orientation: what is returned, that it is deterministic, and where to go for schema details. No important calling context is missing.

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 tool has no parameters and the schema is an empty object, so there is no parameter semantics to explain. The 0-parameter case is the baseline 4, and the description needs no additional parameter detail.

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 resource (deterministic formula registry) and what it returns: id, site, summary, input names, and citations. It also distinguishes itself from canon_describe_formula by explicitly pointing to that sibling for schema details.

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?

Names the relevant alternative canon_describe_formula and the exact condition for choosing it ('for a schema'). The first sentence establishes the list use case, so an agent knows when to call this tool rather than its sibling.

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