list_charts

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

With no annotations, the description carries full behavioral disclosure. It explicitly states 'Read-only against the document,' details the exact per-chart fields including supported_for_update with refusal reasons, and explains chartex naming. This goes well beyond the minimum.

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 front-loaded with the core action, then packs every relevant detail into a single, well-structured sentence block. No filler or repetition; the length is justified by the richness of the output.

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 scope, ordering, output fields, downstream usage, refusal reasons, and safety. An output schema exists to formalize return structure, so nothing essential is missing for an agent to invoke this correctly.

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?

The schema provides no description for file_path (0% coverage), and the tool description never mentions it. Its role is inferable from the tool name and 'document' references, but the description does not explicitly state that file_path identifies the target document. Minimal viable, but a clear parameter definition would be better.

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?

Description opens with a specific verb and resource: 'Enumerate every chart in the document body, in document order.' It clearly distinguishes this from siblings like list_tables and add_chart, and the output fields are precisely scoped to chart inspection.

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 gives clear usage context: the returned index is explicitly linked to update_chart_data, and the read-only nature implies safe inspection. It does not list alternatives or exclusion conditions, but for a listing tool this is sufficient context.

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