video_ocr

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

With no annotations, the description carries the full burden and does so: it discloses that it downloads only the lowest-quality segment, that cost is ~0.3–0.8s per frame on CPU, that the OCR engine is a ~80MB optional dependency, and exactly what install=false vs install=true do. This is unusually rich operational context.

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?

Front-loads the core action and the trigger condition, then cost, then the install caveat — a sensible order. Markdown emphasis and quoted phrasing add some visual noise, but no sentence is 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 6-parameter tool with no output schema and no annotations, it covers purpose, trigger, cost, dependency handling, and that results carry timecodes. Only the width parameter and the exact result shape (beyond 'timecoded, directly quotable') are left unexplained.

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 coverage is 0%, so the description must compensate, and it explains n (number of sampled time points, 12 for a 5–6 minute video) and install (in-place engine download vs. reporting the install location). start/end are implied by 'only download this segment' and url is self-evident, but width is never explained.

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 and resource: read text on screen via local offline OCR, explicitly noting it does not use audio or platform subtitles. This clearly separates it from siblings like video_subs (subtitles) and video_visual_scan (general visual scanning).

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 an explicit trigger condition — use it after video_brief reports 'almost no speech, text all on the picture' — and names the alternative scenario it is not for. The routing logic is directly actionable.

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