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

Annotations already declare readOnly, idempotent, closed-world and non-destructive, so safety is covered. The description adds two genuinely new behavioral facts: the fixed result count of 12 and a cost of 2 credits, which matters for a paid API. It says nothing about failure modes when an id has no neighbors, which keeps it below a 5.

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?

Two compact clauses, no filler: the result shape leads, the parameter provenance follows, and the credit cost is a single trailing token. Every element earns its place and nothing needed to be cut.

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 two-parameter read tool whose annotations and absent output schema lower the disclosure burden, the description covers result count, source of inputs, and cost. The remaining gap is real though: with no enum and 0% schema coverage, an agent cannot know the legal values for 'source' without trial and error.

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% and neither parameter has a type explanation, enum, or example, so the description carries the full burden. It does tell the agent where to source 'source' and 'id' (search_content), but never explains what values 'source' accepts or what format 'id' takes, leaving the highest-risk field undocumented.

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 states a concrete output (12 semantically similar videos) for a concrete input (one TRYIT item), and it points at search_content as the place the item comes from. It stops short of distinguishing this from find_original, a sibling whose 'original vs similar' purpose could easily be confused with this one.

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?

"use source + id from search_content" gives an explicit prerequisite and a routing instruction, so an agent knows this is a follow-up call after a search, not a standalone entry point. It does not say when to prefer this over find_original or what to do if no similar items exist, so it stops short of full when/when-not guidance.

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