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

With no annotations, the description carries the full burden and does disclose several behavioral traits: upsert semantics, the clear-on-empty behavior, and the v1 single-file limitation. It omits permissions/auth requirements and return behavior, which keeps it from a 5 for a mutation tool.

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-loaded with the core action, then the clearing rule and versioning caveat. The future-versions sentence is slightly speculative but is short and helps set expectations; overall tight with minimal waste.

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 write tool with no annotations and no output schema, the description covers purpose, clearing semantics, and version scope. What remains missing (return shape, overwrite/conflict behavior, permissions) are gaps but not disqualifying; the schema already handles argument documentation.

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 all four parameters are already documented in the schema. The description's only parameter-relevant detail (omit/empty content clears the body, AGENTS.md as conventional name) is already repeated in the schema descriptions, adding no new meaning. Baseline 3 applies.

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: 'Upsert a named markdown file on a board.' It goes further to position itself against a sibling, naming update_board's prompt option as the higher-level path, so an agent can distinguish it without opening 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?

It gives a clear usage rule ('Omit content (or pass empty) to clear a file's body') and a routing hint ('low-level writer beneath update_board's prompt option'), which implies when to prefer the sibling. It stops short of an explicit when-not-to-use-this instruction, so it falls just short of 5.

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