meta_ads_pages_upload_photo

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

With no annotations provided, the description carries the full burden and does so thoroughly. It discloses that the operation is mutating ('Mutating (creates a Page photo)'), not automatically reversible, uploads UNPUBLISHED, requires the pages_manage_posts permission and Page Access Token, and includes a notable quirk about the one-way write field and Meta rejecting context_card{cover_photo_id}. This goes well beyond a simple 'creates a photo' statement.

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?

The description is long but exceptionally dense. Every sentence earns its place: purpose, distinction from sibling, typical flow, a verification gotcha, required parameter exclusivity, publication status, auth requirement, and mutability. It is front-loaded with the primary action and returns value, then builds context. No filler or repetition.

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 tool with no output schema and no annotations, this description is remarkably complete. It covers the action, return value, use case, integration flow with lead form creation, a common failure mode and how to avoid it, parameter constraints, permission requirements, and write side effects. An agent has everything needed 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?

The schema already covers all 4 parameters with descriptions (100% coverage), so baseline is 3. The description adds meaningful semantic emphasis by stating 'Provide exactly one of file_path (local image) or image_url' and by explaining the purpose of the resulting photo_id in relation to the lead form context_card. It doesn't re-document every parameter, but it clarifies the critical output-to-input relationship that the schema alone does not convey.

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 uses a specific verb+resource: 'Uploads a photo to a Facebook Page and returns its PAGE photo id.' It clearly distinguishes itself from the sibling meta_ads_images_upload_file by explaining the crucial difference between a Page photo id and an ad-account image_hash, and even names the exact use case (Instant Form cover photo). This is far more than a tautology or vague purpose.

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 description gives explicit when-to-use guidance: 'Typical flow: upload here → take photo_id → pass it as context_card.cover_photo_id to meta_ads_lead_forms_create.' It also tells users when NOT to use it (the image_hash from meta_ads_images_upload_file does NOT work) and provides an alternative verification path (meta_ads_lead_forms_get). This is exemplary usage guidance.

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