Guide to CUB cloud APIs in Lampa

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

Annotations already declare readOnlyHint/idempotentHint/destructiveHint; the description reinforces and expands this with 'pure snapshot read' and 'makes no network calls of its own', and documents per-topic ignore/require behavior that annotations cannot convey. No contradiction with annotations was found.

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?

At roughly 150 words it is dense, but each clause covers one of the six topic modes and front-loads the core purpose and safety. No filler; the semicolon-delimited topic map is the most efficient way to convey the matrix of valid parameter combinations.

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 six topics and seven parameters, the description enumerates every topic's valid inputs and ignored fields, plus the tool's relationship to external docs and related tools. Given an output schema exists, not describing return values is acceptable; nothing needed to invoke it correctly 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?

Schema covers all 7 params, so baseline is 3, but the description adds high-value cross-parameter constraints: `endpoint` requires `path` and ignores `category`/`search`, `auth` reads only `auth_focus`, `sync` takes no parameters, and `timeline_hash` reads only `example`. These interdependencies are not inferable from individual property descriptions.

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 uses 'Document how Lampa talks to CUB from source' – a specific verb and resource – and immediately separates it from `list_catalog` topics and cub.rip/developer, making the tool's CUB-specific scope unmistakable. It clearly distinguishes this from sibling tools without needing to open the schema.

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?

It gives explicit when-not guidance ('not a substitute for cub.rip/developer') and contrasts with the sibling `list_catalog` topic=mirrors/socket, making alternative selection concrete. The per-topic parameter rules also tell the agent exactly which parameters to provide for each mode, reducing guesswork.

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