Charts: update

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

Adds behavioral detail well beyond the annotations: partial-update semantics (unpassed settings persist), the destructive-replace behavior of `filter`, and the non-obvious propagation that dashboard widgets reference the chart rather than copy it, so every dashboard redraws. It also reinforces the user-confirmation requirement consistent with destructiveHint=true.

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?

Front-loads the purpose and keeps each sentence short and on-task, with the safety caution last where it belongs. Mild redundancy between 'Only the settings you pass change' and 'Saves new settings on an existing chart', plus a low-value 'Returns JSON.' line, keep it from a 5.

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 26-parameter mutation with no output schema, the description covers the essentials: partial-update behavior, filter replacement, propagation side effects, prerequisite read, and confirmation. The only weak spot is the vague 'Returns JSON.' in place of any return-shape hint, though the absence of an output schema makes this a minor gap.

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 100% across all 26 parameters, so the schema already carries the parameter documentation and the baseline is 3. The description adds only the filter-replacement rule, which is also stated in the schema, so there is no meaningful extra parameter insight.

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 and resource ('Change a chart') and immediately qualifies it as a partial update against an existing chart, which separates it from charts_create. It also names charts_get as the read-side sibling to consult first, so an agent can route correctly without opening other schemas.

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?

Gives concrete pre-call guidance ('Use charts_get first to see its current settings') and a confirmation rule ('check with the user before running it'). It doesn't explicitly state when NOT to use it (e.g., to create a chart, use charts_create), but the context is clear.

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