Your Spotify 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. While it clarifies the scope (affects Your Spotify profile, not actual Spotify account), it doesn't mention important behavioral aspects like whether this requires authentication, if changes are reversible, rate limits, or what happens to existing profile data. For a mutation tool with zero annotation coverage, this is insufficient.

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 efficiently structured with two clear sentences stating the purpose and scope, followed by helpful example queries. Every sentence earns its place, and the information is front-loaded with the core functionality stated first.

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 single-parameter mutation tool with no annotations and no output schema, the description provides adequate basic information about what the tool does and its scope. However, it lacks details about behavioral implications, error conditions, or what happens after execution, which would be valuable given the mutation nature of the operation.

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?

The description doesn't explicitly mention the 'new_username' parameter, but with 100% schema description coverage (the schema fully documents the parameter with constraints), the baseline is 3. The description adds value through example queries that demonstrate parameter usage in context, showing how the parameter fits into natural language requests.

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 specific action ('Change your display username') and resource ('in Your Spotify'), distinguishing it from sibling tools like 'update_user_settings' which likely handles broader settings. It explicitly notes this affects only the Your Spotify profile, not the actual Spotify account, providing important scope clarification.

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 clear context about when to use this tool (to change display username in Your Spotify) and includes example queries that illustrate typical use cases. However, it doesn't explicitly state when NOT to use it or mention alternatives like 'update_user_settings' for other profile changes.

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