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

With no annotations, the description carries the full burden and does disclose the two traits that matter most: the operation is a destructive full replacement, and it is confirm-gated so an unconfirmed call only previews. It does not cover permission/auth requirements or whether invalid image references are rejected, so it is strong but not exhaustive.

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 sentences, front-loaded with the destructive replace semantics followed immediately by the confirm-gate and the read-before-write hint. No filler or restated field names.

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 mutation tool with no annotations and no output schema, the description covers the riskiest aspects (full-list replacement, preview-vs-execute confirm). The remaining gap is the shape of each transformation entry, though the schema's required array exposes those fields, keeping the omission minor.

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 50% (only 'confirm' is documented in the schema), so the description must compensate. It does the critical work by stating 'Sends the full list,' clarifying that the transformations array is a complete replacement rather than a patch or append. It adds no detail on the six required nested item fields (clientName, timeline, images, goal, results), which remain undocumented.

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 verb and resource: 'Replace the coach's own public before/after client transformation gallery.' It scopes it to the coach's own gallery, which cleanly distinguishes it from siblings like update_my_testimonials, update_my_professional, and update_organization_profile.

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 gives a concrete routing rule: 'read get_my_profile first if only adding one,' naming both the alternative tool and the condition that selects it, plus the confirm-gated execution note. It stops short of stating when not to use the tool at all, but the guidance is clear and actionable.

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