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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuine value beyond that by disclosing the negative scope ('Does not install or run anything') and by enumerating what the response contains in the absence of an output schema.

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?

A single sentence that front-loads the core action and identifier, then lists the payload compactly, ending with the negative scope. No filler and nothing is buried.

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?

With no output schema and no parameter descriptions, the description usefully compensates by itemizing the returned fields and confirming this is a read-only lookup. It omits what happens when the slug is not found, which is the only notable gap for a one-parameter read tool.

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 'slug' parameter carries only a regex pattern with no prose. The description supplies only 'by slug' as its meaning, which conveys that it is the identity key but adds little about format or lookup failure behavior.

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 and resource ('Read one RUAGENTIC listing by slug') and enumerates the returned payload (facts, stars, connection details, Q&A). The singular 'one ... by slug' framing cleanly separates it from listing/search siblings like search_directory, top_listings, and new_listings without needing to name them.

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?

Usage is implied by the 'one listing by slug' framing and the exclusion 'Does not install or run anything' pushes the agent away from execution-style intent. However, it never explicitly names an alternative (e.g. connect_instructions for setup steps or compare_listings for comparisons) or states the condition that would select this tool over them.

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