keybase_lookupLook up a Keybase user by username to retrieve linked social accounts and public keys.
Look up a Keybase user and their linked social accounts / public keys.
| Name | Required | Description | Default |
|---|---|---|---|
| username | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds the result scope (linked social accounts and public keys) but does not disclose any additional behavioral details such as error cases, rate limits, or prerequisites.
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?
A single concise sentence front-loads the verb, resource, and expected outputs. There is no filler, repetition of the title, or unnecessary detail.
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?
The tool is a simple read-only lookup with one parameter and an output schema, so the description is largely sufficient. It only lacks explicit parameter format guidance and alternative routing, which are minor gaps given the low complexity and existing annotations.
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 for the undocumented username parameter. It only restates that the lookup is for a 'Keybase user', adding little beyond the schema's property name. No format, example, or constraint is given.
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 ('Look up'), a specific resource ('a Keybase user'), and the data scope ('linked social accounts / public keys'). It clearly identifies this as a Keybase-specific OSINT tool, distinguishable from the many DNS/IP/email siblings in the tool list.
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 usage context is implied: use this when you need Keybase account linking information. However, the description provides no explicit guidance about when not to use it or which sibling tools might be alternatives, such as username_enumerate or gravatar_lookup.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.