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

Adds substantial context beyond annotations: merge semantics ('Shared template_values merge recursively... arrays, scalars and explicit null replace defaults'), template_id/version reset behavior, deduplication ('Identical images reuse existing assets'), and return format. Doesn't contradict annotations. Missing explicit statement about the destructiveHint=true implication (e.g., overwrite semantics) and plan limit details, but otherwise covers behavioral traits well.

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?

Dense but front-loaded: core purpose first, then operational constraints. Every sentence carries information, though the description is somewhat long and could be structured with bullets for the merge rules. 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?

Output schema exists, so return value explanation isn't required, yet the description still notes 'Returns IDs, URLs and format information in response order' which is helpful. Covers batch workflow prerequisites (get_max_batch_size, list_templates) and merge semantics. Missing explicit note on destructiveHint=true/overwrite behavior and plan limit details.

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 100%, so schema already documents both parameters in detail. Description reinforces merge behavior and ID resolution which are informative but largely duplicates schema guidance. Baseline 3 is appropriate.

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+resource: 'Creates multiple images from one or more saved templates.' Clearly distinguishes from create_templated_image ('Use create_templated_image for a single image') and from create_batch_images, and names it explicitly.

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?

Explicit when-to-use and alternatives: 'Call get_max_batch_size first', 'resolve unknown IDs with list_templates', 'Use create_templated_image for a single image or inline preview.' Names specific sibling tools and the conditions that select them.

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