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

Goes beyond the annotations by disclosing placement behavior ("Appended in reading order unless gridPos places it") and persistence ("Saved when this runs"), plus the human-facing effect of reason on an approval card. With readOnlyHint=false and idempotentHint=false already declared, this is meaningful added context, though it doesn't say what is returned or what happens on a failed/invalid content save.

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?

Five short sentences, each doing distinct work: purpose, sibling exclusion, placement default, persistence plus reason guidance, and the skill prerequisite. Purpose and the exclusion are front-loaded, and nothing is redundant.

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 6-parameter mutation tool with a nested gridPos object, the description covers purpose, alternative, placement defaults, persistence, and the required skill. The only gap is the absence of any return-value note, which matters slightly since there is no output schema.

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 100%, so the baseline is 3, but the description adds semantics the schema lacks: the default 6x8 panel size and the default placement order that applies when gridPos is omitted. That clarifies the optionality and consequences of gridPos beyond its own field descriptions.

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 ("Add a markdown text panel to a dashboard") and immediately clarifies what that resource is ("a card of notes explaining the charts around it"). It also names the sibling it is not — add_heading_panel — so an agent can distinguish the two without opening either schema.

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?

Explicit when-not guidance: "For a section title use add_heading_panel instead." Adds a prerequisite (load the manage-dashboards skill first) and a call-convention (explain it in reason), covering both selection and invocation context.

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