Etsy MCP Server

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. While 'Create' implies a write/mutation operation, the description doesn't disclose important behavioral traits like whether this requires specific permissions, what happens if the receipt already has a shipment, whether tracking is mandatory, or what the response looks like. For a mutation tool with zero annotation coverage, this leaves significant 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 a single, efficient sentence that gets straight to the point with zero wasted words. It's appropriately sized for a tool with clear parameters and no complex behavioral nuances needing explanation.

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 mutation tool ('Create') with no annotations and no output schema, the description is incomplete. It doesn't address what happens after creation (success response, error conditions), whether the operation is idempotent, or any side effects. Given the complexity of creating a shipment with tracking, more contextual information would be helpful for the agent.

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%, meaning all parameters are documented in the schema itself. The description adds no additional parameter semantics beyond what's already in the schema (e.g., it doesn't explain relationships between parameters like shop_id and receipt_id, or clarify what 'send_bcc' actually does). With complete schema coverage, the baseline score of 3 is appropriate.

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 action ('Create a shipment with tracking') and the target resource ('for a receipt'), which provides a specific verb+resource combination. However, it doesn't explicitly differentiate this tool from potential sibling tools like 'update_shipping_profile' or 'manage_shipping_destinations' that might also handle shipping-related operations.

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. It doesn't mention prerequisites (e.g., whether authentication is required), when this should be used instead of other shipping-related tools, or any constraints on its usage. The agent must infer usage from the tool name and parameters alone.

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