upload_file

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

Adds substantial behavior beyond the annotations: overwrite=true is the only path that permits replacement, the response separates acceptance, actual location, and content verification, and an unverified/unknown result must be inspected before retrying. This is consistent with destructiveHint=true and idempotentHint=false.

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?

Front-loads the core action and constraints, then covers overwrite semantics, return behavior, retry guidance, and the ZIP edge case. Every sentence adds operational value with no 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?

For a destructive, non-idempotent mutation tool with no output schema, the description explains the dangerous parameter, the meaning of the return result, and how to handle uncertain outcomes. Combined with annotations and the input schema, an agent has what it needs to invoke 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 0%, so the description carries the burden and mostly succeeds: it explains localPath as an absolute server-side path, path as project-relative with a basename default, and overwrite's default and destructive effect. projectId is only implied by 'existing project folder' rather than explicitly described.

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?

States a specific verb and resource ('Upload one local file') and scopes it to an existing project folder. The ZIP clarification further distinguishes this from project-import behavior, so an agent can separate it from siblings like write_file or create_file without opening schemas.

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?

Gives clear operational context: localPath must be absolute on the MCP server, path defaults to the basename, and overwrite defaults to false. It also includes an important exclusion ('ZIPs are uploaded as files, not imported as projects'), though it does not explicitly name sibling alternatives such as write_file.

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