Add chart indicator

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

Annotations provide readOnlyHint=false and destructiveHint=false, but the description adds no behavioral context. It doesn't explain what happens when an indicator is replaced (e.g., whether existing indicators are overwritten), whether the operation requires a valid chart state, or any side effects. With no additional behavioral information, the description fails to add value beyond the annotations.

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, concise sentence that efficiently lists the supported indicator types. It is appropriately short and front-loaded, with no redundant information. However, it could be slightly more structured, perhaps by explicitly noting that different indicator types use different parameters, but it's still very tight.

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 tool's complexity (8 parameters, multiple indicator types with different parameter requirements), the description is insufficient. There is no explanation of which parameters apply to which indicator type, no mention of output or side effects, and no guidance on how 'replace' works relative to 'add'. The annotation set is minimal, and there is no output schema, so the description must carry more weight for both usage and behavior.

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%, meaning the description provides no parameter details. The schema itself defines parameters like kind, period, fastPeriod, etc., but the description only lists the acceptable indicator types without explaining which parameters apply to each kind. For example, 'standardDeviations' is only relevant to Bollinger Bands, but the description doesn't clarify this, leaving the agent to guess. The description should compensate for the low coverage.

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 function: 'Add or replace an SMA, EMA, Bollinger Bands, RSI, or MACD study.' It uses a specific verb (add or replace) and specifies the resource (chart indicator). It distinguishes from siblings like chart_remove_indicator and chart_apply_overlays, though it doesn't explicitly differentiate between 'add' and 'replace' in terms of when one happens.

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 no guidance on when to use this tool over alternatives, such as when to use a specific indicator type or how to choose between 'add' and 'replace'. It is clear that this is for adding indicators, but there is no mention of prerequisites (e.g., chart must be open), nor any exclusions or alternative tools that might be more appropriate for other scenarios.

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