Upload an image to Ghost

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

Annotations already declare readOnlyHint=false, destructiveHint=false, idempotentHint=false, and openWorldHint=true, so the safety profile is covered. The description adds genuinely new behavioral facts: the sandbox root GHOST_UPLOAD_ROOTS, the 20 MB ceiling, and three explicit refusal classes (remote URLs, SVG, symlink escapes). It omits auth requirements and what happens on success.

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?

One dense sentence with zero filler. The accepted case is front-loaded and the refusal list follows compactly, so the reader gets the contract in a single pass.

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?

An output schema exists, so return values need not be explained, and the input contract's rejection rules are fully stated. The remaining gap is operational detail around path format and permissions, which an agent would need to call this correctly on the first try.

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 0% and the single 'path' parameter has no description, so the description must carry the load. It does convey that the value is a filesystem path constrained to GHOST_UPLOAD_ROOTS, but it never clarifies absolute vs relative form, extension expectations, or whether the file must already exist.

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?

Specific verb ('Upload') plus resource ('an image to Ghost') with the source narrowed to 'a local image inside GHOST_UPLOAD_ROOTS'. No sibling tool performs uploads, so even without a named alternative an agent can place it immediately.

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?

It states clear usage boundaries: files must be local and under GHOST_UPLOAD_ROOTS, and remote URLs, SVG, symlink escapes, and >20 MB files are refused. There is no competing sibling to route away from, so no explicit alternative is needed, but nothing states prerequisites such as auth or when an upload should precede publish_posts.

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