list_subscriptionsList the caller's active subscriptions. Returns id, type, params, created_at, last_fired_at, fire_count for each. Use this to review what you're monitoring before adding more or to find an id to cancel.
| Name | Required | Description | Default |
|---|---|---|---|
| include_inactive | No | Include cancelled subscriptions in the response (default false). |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is known. The description adds behavioral context by specifying the return fields (id, type, params, etc.) and scoping to active subscriptions. No contradictions with annotations.
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 two sentences: the first states the action and return fields, the second explains use cases. Every sentence earns its place, and it is front-loaded with the purpose.
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 the tool's simplicity (one optional parameter, no output schema) and strong annotations, the description is complete. It covers the scope (caller's subscriptions), return fields, and practical use cases. It doesn't mention include_inactive, but the schema fully covers that.
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 100% for the single optional parameter include_inactive, which has a clear description. The tool description does not add any additional information about this parameter, so it relies entirely on the schema. Baseline of 3 is appropriate given perfect schema coverage.
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 the verb 'List' with the specific resource 'the caller's active subscriptions,' clearly stating what the tool does. It distinguishes itself from sibling tools like subscribe/unsubscribe by focusing on read-only listing. It also lists the exact return fields, leaving no ambiguity.
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 explicitly states when to use this tool: 'to review what you're monitoring before adding more or to find an id to cancel.' This provides clear context for the tool's role in the subscription workflow. However, it doesn't explicitly name alternative tools like subscribe/unsubscribe, though the context implies them.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
The server is named 'spacex' but contains a vast number of tools unrelated to SpaceX, such as polymarket arbitrage, npm package scanning, and claim validation. Users and agents would struggle to determine whether this server is for SpaceX data or general-purpose queries.
The SpaceX-specific tools follow a consistent 'get_' pattern, but the majority of tools use varied naming conventions (e.g., 'ask_pipeworx', 'bet_research', 'remember', 'subscribe'). No unifying pattern across the set.
36 tools is a moderately large count, not extreme. However, many tools are unrelated to the server's namesake, making the set feel bloated and unfocused. The count could be trimmed to improve coherence.
For the SpaceX domain, the coverage is decent (launches, rockets, crew, Starlink). But the server's purpose is unclear—there are glaring gaps in a unified vision, as the Pipeworx tools are not integrated into a coherent SpaceX theme.