add_to_selection

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

With no annotations, the description carries the full burden and delivers: it reveals that Ozon only draws from favorites and silently drops invalid items, plus instructs checking the returned items count. This goes well beyond the schema and is critical for correct invocation.

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 dense sentences: the first states the core function with an important nuance, the second provides a critical prerequisite and a practical check. No filler or redundancy; every word earns its place.

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 description covers the gating condition (writes_enabled), the prerequisite (favorites), the mutation semantics (keep existing items), the silent-drop risk, and the follow-up action (check items count). With an output schema present, no return format details are needed; this is complete for the tool's complexity.

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% and both parameters (skus and uuid) are already documented clearly in the input schema, including the uuid's origin from list_selections()[].uuid. The description adds no further parameter-level detail, which is acceptable at baseline.

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 states the action: 'Add products to a «Подборка»' with the specific nuance 'keeping what is already in it', which distinguishes it from sibling tools like set_selection_items or remove_from_selection. The resource and scope are 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?

The description provides explicit conditional context: products must be in favorites first, and it warns about silent drops. It implies incremental addition (vs replacing) but does not name alternative tools or explicitly state when not to use it, so it lacks full exclusion guidance.

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