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

No annotations are provided, so the description bears the full burden. It does not disclose output format (e.g., base64, file path), potential side effects, or resource implications of server-side generation. It mentions rules for usage but not behavioral traits like mutability or return structure. The 'self-invocation prohibition' is a usage guideline, not a behavioral disclosure.

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 concise and well-structured, front-loading the purpose and then providing usage constraints. It packs important rules into a few sentences without unnecessary fluff. Slightly long due to the list of indicators, but still efficient.

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?

With 22 parameters, nested objects, no output schema, and no annotations, the description is far from complete. It gives essential usage rules but omits output expectations, error scenarios, and explanations for most parameters. The description would need to be substantially richer to fully guide an agent.

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 only 41%, and the description compensates for only a few parameters: it instructs not to set indicators unless explicitly requested, and notes that overlays can be passed from detect_patterns. However, it does not explain many other parameters (depth, limit, style, bbMode, ichimoku, subPanels, etc.), leaving significant gaps for such a large parameter set.

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 specific verb (generate) and resource (candlestick/line charts to SVG/PNG server-side), and explicitly differentiates from prepare_chart_data for client-side rendering. It also mentions overlays from detect_patterns, clearly setting it apart from other rendering tools.

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?

Provides explicit routing: prefer prepare_chart_data if client-side rendering is possible, only use when the user explicitly requests SVG/PNG save, and prohibits spontaneous calls. Also specifies that indicators must be user-requested, leaving no ambiguity about when to invoke.

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