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

Annotations already indicate readOnlyHint=false, destructiveHint=false, and idempotentHint=false, so the description adds value by disclosing the rate limit, the fact that only 32 bytes reach the log, and the privacy guarantee for local file hashing. It also clarifies the trust model (7 witnesses, 6 operators, Bitcoin anchoring) and the non-repudiation limits, which are not visible in 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 dense but well-organized, front-loading the core action and then layering constraints and use cases. It is longer than strictly necessary, but every sentence adds meaningful context (privacy, rate limit, proof contents, limitations). The structure flows logically from action to details to typical use.

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 tool with no output schema, the description compensates well by describing the receipt contents (leaf index, inclusion-proof URL, c2sp.org/tlog-proof bundle URL, witness trust policy). It also covers the main edge cases (hosted server refuses path, rate limit, hash-only mode). The only minor gap is that it doesn't specify the exact format of the receipt or error behavior, but the description is strong enough for an agent to invoke it correctly.

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%, so the schema already documents both parameters. The description adds context about the 'sha256:' prefix and the local-only nature of the path parameter, but it doesn't go beyond what the schema already conveys. Baseline 3 is appropriate because the schema carries the heavy lifting.

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 states a specific verb ('Notarize') and resource ('any file or hash into a public transparency log'), and clearly distinguishes the tool from siblings by explaining what it does not prove (authorship or truthfulness). It also differentiates the two input modes (hash vs file path), making the tool's purpose unmistakable.

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 explicitly says when to use this tool ('Typical use: notarize an output the moment it is produced') and what it does NOT do ('does NOT prove authorship or that the content is true'), which helps an agent avoid misuse. It also notes rate limits (10/hour) and the hosted server's refusal of file paths, giving clear operational boundaries.

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