Rebillia MCP Server

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

With no annotations provided, the description carries full burden for behavioral disclosure. It states this is a GET operation (implying read-only) and mentions an optional parameter, but doesn't describe authentication needs, rate limits, error conditions, response format, or whether it's idempotent. For a read operation with zero annotation coverage, this leaves significant behavioral gaps.

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?

The description is extremely concise (two short sentences) with zero wasted words. It's front-loaded with the core purpose. However, the inclusion of the API endpoint 'GET /subscriptions/{subscriptionId}' is redundant with the tool name and doesn't add value for an AI agent, slightly reducing efficiency.

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?

For a read operation with no annotations and no output schema, the description is incomplete. It doesn't explain what a subscription object contains, what the 'include' parameter actually includes, or what the response looks like. Given the complexity of subscription data and the lack of structured output documentation, more context is needed for effective use.

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 100%, so the schema already documents both parameters fully. The description mentions 'Optional: include' but adds no meaning beyond what the schema provides about the 'include' parameter. With complete schema coverage, the baseline is 3 even without additional param semantics in the description.

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 clearly states the verb ('Get') and resource ('a subscription by ID'), making the purpose unambiguous. It distinguishes from siblings like 'list_subscriptions' (which retrieves multiple) and 'get_customer_subscriptions' (which filters by customer). However, it doesn't explicitly contrast with these alternatives in the text itself.

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 provides no guidance on when to use this tool versus alternatives like 'list_subscriptions' or 'get_customer_subscriptions'. It mentions an optional 'include' parameter but doesn't explain when to use it or what it does. No prerequisites, exclusions, or comparative context are provided.

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