Look up a physical constant by alias, exact name, or keyword to get its value, unit, and uncertainty for unit-aware physics calculations.
Look up a physical constant by alias, exact name, or keyword; return value, unit and uncertainty.
| Name | Required | Description | Default |
|---|---|---|---|
| query | Yes |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden. It usefully discloses the return payload (value, unit, uncertainty), but says nothing about ambiguous matches, no-match behavior, or case sensitivity — the failure modes an agent would actually hit.
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?
One sentence, front-loaded with the action and resource, ending with the return contract. No filler.
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, and the description supplies the return shape (value, unit, uncertainty), which covers the main gap. Missing only edge-case behavior for ambiguous or unmatched queries — minor for a simple read-only lookup.
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 0% and the schema only labels the field 'Query', so the description must compensate. Listing alias, exact name, and keyword as accepted input forms adds genuine meaning about matching strategy, though it does not specify case handling or fuzzy vs exact precedence.
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?
Specific verb (look up) plus resource (physical constant) plus accepted query forms (alias, exact name, keyword). No sibling tool performs constant lookup — unit_convert and unit_calculate operate on quantities — so the resource alone differentiates it.
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 names the three query forms, which implies how to invoke it, but gives no when-to-use guidance, no exclusions, and no pointer to alternatives such as unit_calculate. Usage is inferred rather than stated.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.