photos_add_to_album

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

Annotations only include destructiveHint:false, so description carries some burden. It discloses requirements (authentication, path format, pre-existing photo) but does not mention what happens on failure (e.g., album not found, photo already in album) or whether the operation is idempotent. It clarifies a non-obvious behavioral trait (does not upload), but leaves other side effects unspecified.

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?

Three concise, front-loaded sentences. The first sentence states the core purpose; the second sets path constraints; the third clarifies a boundary and points to a helper tool. No redundant 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 simple two-string-parameter tool with no output schema and minimal annotations, the description covers purpose, usage constraints, and a key behavioral caveat. It lacks explicit error-handling information but is sufficiently complete for an agent to select and invoke the tool 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 already covers both parameters with descriptions and examples (100% coverage), so baseline is 3. The description adds value by clarifying that photoPath must reference an existing library item and that the tool does not upload, plus suggesting photos_list_albums to discover albumPath. This enriches parameter meaning.

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?

Clearly states the action (add a photo) with source (library) and destination (album), distinguishing it from sibling tools like photos_remove_from_album or photos_create_album. The verb 'Add' and resource phrasing are specific.

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?

Provides explicit usage conditions: requires authentication, path prefixes, photo must already exist (not for upload), and points to photos_list_albums for finding album paths. This effectively tells when to use and when not to use.

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