add_deneb_visual

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

With no annotations provided, the description carries the full burden. It discloses internal behaviors: registers guid, adds visual, binds dataRoles, and writes objects.vega[0].properties with specific formatting details. It also includes a caveat about visualGuid defaulting to the published guid, adding transparency about a potential misconfiguration. It does not cover all side effects (e.g., overwriting, errors) but is above average.

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?

The description is a single dense sentence but efficiently packs all essential information. It is front-loaded with the main action and then details sub-operations. Slightly overlong and could benefit from bullets, but every sentence earns its place with no waste.

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?

Given the complexity (16 params, no output schema, no annotations), the description covers the core behavior and key parameter formats but leaves gaps: it doesn't explain return values, error conditions, or prerequisites like reportSessionId. It also omits semantics for positional parameters x/y/w/h (though those have defaults). It's adequate but not complete for a tool of this 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 coverage is 69%, so the description adds meaningful context beyond the schema. It explains that spec/config are JSON strings (schema already says), dataRoles is a JSON array of {table,field,kind}, provider/renderMode have specific enum-like values, and enable* booleans exist. It also reveals the format of jsonSpec (one-lined + single-quoted in a literal), which is not in the schema. This compensates for the coverage gap.

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 tool's purpose: 'Add a DENEB (Vega / Vega-Lite) custom visual to a page' and enumerates specific actions (registers the Deneb guid, adds the visual, binds dataRoles, writes properties). This distinguishes it from sibling tools like add_visual or register_custom_visual by its Deneb-specific scope and detailed behavior.

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 implies when to use this tool: when adding a Deneb visual to a page, with specifics on how to structure the call (e.g., spec/config as JSON strings, dataRoles array format). It does not explicitly mention alternatives or when-not-to-use, but the context is clear enough for an agent to infer it's the correct tool for Deneb visuals.

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