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

With no annotations, the description carries the full burden; it discloses that output is informational only (no mutation or side effects), names the required certification context, and enumerates the returned content. It does not discuss latency, rate limits, or how unknown refrigerants are handled, but for a simple read-only reference tool this is solid disclosure.

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?

Three short, front-loaded lines with no filler; the returned-field list is dense and useful. Slightly choppy line breaks and no mention of the input format keep it from a 5, but nothing is wasted.

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?

No output schema exists, but the description enumerates the return fields, so the agent knows what to expect. The prerequisite/audience note and the informational-only framing round out the picture; only the input parameter format is unaddressed.

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 0% and the single required parameter 'refrigerant' has no description, type detail, or format hint in the description either. The description enumerates output fields but says nothing about the expected input form (e.g., 'R-410A' vs '410A' vs a numeric ID), leaving the agent to guess the most important input 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 (a refrigerant reference card) and enumerates exactly what fields it returns: GWP, ASHRAE safety class, composition, oil, glide, handling notes. It is clearly a lookup, distinguishable from siblings like pt_lookup or convert_units. It does not explicitly name an alternative for when a different refrigerant query is wanted, so it falls just short of 5.

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?

Gives audience and prerequisite context ('For certified HVAC technicians (EPA 608; A2L certification where required)') and flags 'Informational only', which implies it is not a calculation tool. However, it never says when to prefer this over pt_lookup, pt_reverse, or the other refrigerant-property siblings, so routing is left to inference.

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