Get the log key

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

Adds real behavioral context beyond the annotations: creation on first use (which explains readOnlyHint=false), the idempotent nature of re-fetching, output formats (ES256, 64 bytes x‖y, hex/base64/SPKI PEM), and the security property "Never returns private key material." That is genuinely non-obvious disclosure, though it does not touch auth requirements or error modes.

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 core action and return shape before drilling into the variants, with no filler sentences. The prose is dense and slightly run-on with nested clauses, but every clause carries information.

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 single optional enum parameter with full schema coverage, present annotations, and no output schema, the description supplies everything needed: what is returned, in what encodings, the side effect, and the security guarantee. Nothing an agent needs to call it correctly is missing.

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; the description earns above baseline by explaining downstream implications of the choice (a grant naming another key cannot carry statements this server signs; "authority" signs grants that issue_grant makes). This adds meaning the enum label alone does not convey.

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 precise verb and resource ("Return the public half of one of this server's keys") and immediately disambiguates the two variants ("log" vs "authority") with concrete operational meaning. An agent can distinguish this key-fetch tool from siblings like issue_grant or register_statement without opening any 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?

Explains clearly what each "which" value selects and notes the default, giving solid context for choice. It stops short of explicit when-to-use/when-not framing (e.g., prerequisites relative to issuing or registering grants), but the variant guidance is unusually rich.

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