Look up the Roblox engine API

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

Annotations already establish read-only and non-destructive behavior. The description adds meaningful context beyond those annotations: the source is a live, authoritative dump, and the lookup exposes security level, deprecation, and thread safety. No contradictory behavioral claims are made.

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 filler: the first defines the tool's resource and output detail, the second provides concrete usage guidance. Key information is front-loaded and every phrase 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?

Given no output schema, the description compensates well by summarizing both the lookup scope and the returned information categories. It is adequate for an agent to select and call the tool correctly, though an explicit mention of return shape or error behavior would make it fully 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 high (80%), so parameters are already documented in the input schema. The description adds only broad context about member kinds ('properties, methods, events and callbacks') but does not meaningfully explain filter, max_tokens, or include_inherited beyond what the schema provides.

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 verb and resource: 'Authoritative signature lookup from the live Roblox API dump', enumerating precisely what is returned (properties, methods, events, callbacks, parameter types, security, deprecation, thread safety). This clearly differentiates it from forum search, bug search, and creator-doc siblings.

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 explicit use cases: 'confirm a method exists', check deprecation or server-only status, and 'find the right member name before writing Luau'. It does not mention when not to use it or explicitly name alternatives, so it stops short of a full 5.

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