configure_overlay

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

The annotations already declare this is a non-read-only, open-world, non-destructive operation, and the description adds real value on top: it discloses the return payload (configuration URL plus free/Pro tier), the error-recovery behavior (field errors list allowed inputs so you can correct and retry), and a tier limitation on free presets. It does not mention whether reconfiguring is idempotent or overwrites prior config.

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?

Three front-loaded sentences, each carrying distinct information (capability, return value, error behavior, tier caveat), with no filler. Slightly dense in the first sentence where the field list is packed in.

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 7-parameter mutation tool with a nested 'values' object, no output schema, and zero schema description coverage, the description covers outcome, tier gating and error recovery well but leaves parameter semantics and any sibling routing unexplained. Adequate but with clear gaps on the input side.

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 0% across 7 parameters, so the description carries the full burden — but it only echoes five field names ('values, look, aspect, duration or background') without format, ranges, or enum details, and never mentions the two REQUIRED parameters, family and preset. An agent still cannot tell what a valid family/preset value is.

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 ('Configure') and resource ('animated overlay') plus the editable dimensions, so an agent knows it produces a configuration rather than a rendered file. It is distinguishable from render_overlay and get_overlay, though it never names those siblings explicitly.

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?

Usage is implied by the mention of tier gating ('free preset text generally need Pro to render') and the retry-on-field-error note, which hints at an iterative configure-then-render workflow. However there is no explicit when-to-use versus render_overlay or get_overlay, and no stated prerequisites for family/preset.

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