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 well: it discloses the credit cost (1/minute), async job_id behavior, the need to poll via get_job, and a 1-hour expiry on result links. It still omits failure modes and any input caveats beyond what the schema states.

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?

Four tight sentences; the core action is front-loaded and each remaining sentence delivers a distinct operational fact (cost, async polling, expiry) with 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?

No output schema exists, so the description correctly explains returns: synchronous vs. job_id plus polling and link expiry. The only gap is that it never says what a completed (non-async) job returns directly.

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 60%, and the description only reinforces zoom and music; the size enum and seconds_per_image (with its 1-30 bounds) are left entirely to the schema. It adds modest meaning over the structured fields, matching the baseline for partial 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?

States a specific verb+resource ('Turn a set of images into a video slideshow') and names the two major optional behaviors (slow zoom, music track). It is clearly distinguishable from media siblings like edit_video or merge_media, though it does not explicitly say so.

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?

Gives operational guidance for the async path (poll with get_job) and the cost model, which implies when this is worthwhile, but offers no explicit when-to-use vs. alternatives such as merge_media or sprite_sheet.

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