fetch_images_for_alt_fill

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

With no annotations, the description carries the burden for behavioral disclosure. It explains the return contents (image bytes, element_id, source_type, source_id) and the pre-built items template, but it does not explicitly state whether the operation has side effects, requires authentication, or has payload/rate constraints.

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 well-structured with a summary and numbered workflow, making it easy to follow. However, the final sentence redundantly restates the step 3 instruction about filling placeholders, so it is not maximally concise.

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?

The workflow and return format are clearly explained, which is good for a single-purpose helper. But missing parameter semantics, no output schema, and no mention of edge cases or failure behavior leave notable gaps for an agent to safely invoke this tool in all situations.

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 only 40%, with page_id, max_size_mb, and scope lacking descriptions in the schema. The description only mentions using 'scope/limit' and never explains the meaning of the enum values or the other parameters, so it fails to compensate for the low schema coverage.

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 clearly identifies the tool as a one-shot helper for filling image_alt, returning image bytes and element metadata, and distinguishes it from siblings like read_images and set_image_alts by prescribing a specific workflow. The verb 'fetch' plus 'images_for_alt_fill' makes the purpose unambiguous.

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 workflow context: call with scope/limit, receive images and metadata, draft alts, then call set_image_alts once. This effectively tells when to use the tool, though it does not explicitly mention alternatives or when not to use it.

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