TOS MCP Server

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

No annotations are provided, so the description carries full burden. It implies a generation action but doesn't disclose behavioral traits like whether this requires authentication, what permissions are needed, if the URL is time-limited (only hinted by 'expires' parameter), or what the output format is. It's minimal and leaves critical behavior unspecified.

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 with a single phrase, '生成预签名 URL', which is front-loaded and wastes no words. It's appropriately sized for the minimal information it conveys, though this conciseness contributes to low scores in other dimensions due to under-specification.

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 complexity (generating URLs with authentication implications), lack of annotations, and no output schema, the description is incomplete. It doesn't explain what the tool returns (e.g., a URL string), error conditions, or security considerations, leaving significant gaps for an AI agent to understand and use it correctly.

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 parameters are well-documented in the schema. The description adds no additional meaning beyond the schema, such as explaining relationships between parameters (e.g., method choice affects URL usage) or practical examples. Baseline 3 is appropriate as the schema handles parameter documentation adequately.

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 '生成预签名 URL' (Generate presigned URL) states the basic action but is vague. It doesn't specify what resource it operates on (TOS objects), what the URL is for (temporary access), or how it differs from siblings like tos_get_object. It's better than a tautology but lacks specificity and sibling differentiation.

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?

No guidance is provided on when to use this tool versus alternatives. It doesn't mention use cases like sharing temporary access, bypassing direct authentication, or when to choose this over tos_get_object for downloading. There's no context about prerequisites or exclusions.

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