vk_photos_get_chat_upload_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. It states 'Returns an upload link' and 'Access level: read', but does not disclose behavioral traits such as required permissions, error handling, rate limits, or what happens after getting the link. The description is minimal and does not add significant value beyond the basic function.

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 core sentence is concise: 'Returns an upload link for chat cover pictures.' However, the subsequent three lines (VK API method, tool name, section, access level) are redundant and unnecessarily bloat the description. The structure is front-loaded but contains filler.

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 has 4 parameters, no output schema, and no annotations, the description is incomplete. It does not explain the upload workflow, the response format, or how to use the returned link. For a tool that returns an upload server URL, contextual steps (e.g., upload image then call another method) are missing.

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 50% (only chat_id and crop_width have descriptions). The tool description does not elaborate on any parameters, including the undocumented crop_x and crop_y. It does not compensate for the missing schema documentation, leaving ambiguity about the cropping parameters.

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 it returns an upload link for chat cover pictures, which distinguishes it from other photo upload server tools among siblings (e.g., vk_photos_get_messages_upload_server, vk_photos_get_wall_upload_server). However, it includes redundant information (VK API method, tool name, section, access level) that does not enhance clarity.

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. The description merely states its own purpose without mentioning any conditions, prerequisites, or excluding scenarios. Sibling tools for other photo upload contexts are not compared.

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