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

No annotations are provided, so the description carries the full burden. It states that the tool is free, requires no proof, and returns public data. It also mentions that it returns the latest metadata fields or an empty profile if none is published. These are important behavioral traits. However, it does not explicitly state that it is read-only (though implied by 'Read') or discuss rate limits.

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 three sentences, front-loaded with the main purpose. It efficiently conveys purpose, cost, and return fields without any wasted words. Every sentence adds distinct value.

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?

An output schema exists, so the description need not detail return values, but it does list the metadata fields, which adds clarity. It covers the core behavior (reading public profile, free, no proof) and edge case (empty profile). It does not mention error conditions for invalid npub, but for a simple tool this is acceptable.

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 0%, so the description must compensate. The description mentions 'npub' in the first sentence, indicating the parameter's purpose (the Nostr public key). However, it does not explain the expected format (e.g., bech32 or hex) or provide examples. Given only one parameter and partial description coverage, a score of 3 is appropriate.

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 clearly states it reads a public Nostr profile (NIP-01 kind-0 metadata). It specifies the action ('Read an npub's public Nostr profile') and the resource (Nostr profile). However, it does not explicitly distinguish itself from the sibling tool 'authority_publish_nostr_profile' (write counterpart), though the verb 'Read' inherently implies the distinction.

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 provides clear usage context: 'Free, no proof — the data is already public on relays.' This tells the agent that the tool requires no authentication and has no cost, and is suitable for retrieving public data. It does not explicitly state when not to use it or mention alternatives, but the context is sufficient for a simple read operation.

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