wb_media_upload

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

With no annotations, the description carries the full burden of behavioral disclosure. It explicitly warns that the operation REPLACES all existing media, which is critical for a destructive operation. It does not detail other behaviors like validation or response format, but the core destructive consequence is clearly stated.

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?

Two short sentences with no filler. The warning is front-loaded and prominent, and every word contributes useful information. The mixed-language reminder adds clarity for non-English users without bloating the description.

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?

The description covers the essential destructive behavior and the upload mechanism, but it omits guidance on the undocumented nm_id parameter, does not name the alternative file-upload tool, and does not describe expected outputs or failure modes. For a simple two-parameter tool this is adequate but not fully complete.

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 only 50%: 'links' is documented in the schema, but 'nm_id' has no schema description and the tool description does not explain it either. The description adds little to what the schema already says about links, and fails to compensate for the undocumented nm_id parameter.

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 states a specific action ('Upload'), a resource ('photo/video to a card'), and the method ('by URL'). This clearly distinguishes it from the sibling wb_media_upload_file, which presumably handles file uploads instead of URL-based uploads.

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 'by URL' wording implies when to use this tool, but it never explicitly says 'use wb_media_upload_file for local file uploads' or names any alternative. The destructive warning gives context, but there is no direct when-to-use or when-not-to-use guidance.

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