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

With no annotations, the description carries the behavioral burden. It usefully discloses that the tool replaces everything on the board and specifies acceptable content formats, but it omits other mutation-related details such as permissions, reversibility, or error behavior.

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?

Two tightly written sentences front-load the destructive replacement behavior, then add format constraints and an alternative. Every clause earns its place.

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 two-parameter mutation tool with no output schema or annotations, the description provides the essential purpose, destructive behavior, content formats, and an alternative. It could still say more about permissions or failure modes, but it is nearly complete for this complexity.

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 already 100%, but the description adds format-specific meaning for the content parameter: HTML must be a complete inline document and Markdown is GitHub-flavored. This goes beyond the generic schema description 'The new content.'

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 uses the specific verb 'Replace' with the resource 'board' and explicitly states that all existing content is overwritten. It also distinguishes the HTML/Markdown formats and names a sibling tool for a different use case, so an agent can quickly identify its role.

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?

It gives a clear usage context and an explicit alternative for doodling: 'For a doodle, use `draw` instead.' However, it does not contrast with other relevant siblings such as `edit_text`, so the guidance is strong but not exhaustive.

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