discover_capabilitiesSearch the capabilities.txt registry for sites that can do something — by capability id, keyword, or category. Returns matching capabilities with the site that offers them and its conformance grade. To invoke, fetch that site's /capabilities.txt.
| Name | Required | Description | Default |
|---|---|---|---|
| query | Yes | A capability id, verb, or keyword, e.g. "check_stock" or "refund" |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations provided, so description must fully disclose behavior. It describes return values but does not mention side effects (likely read-only), safety, or any limitations.
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?
Three sentences, front-loaded with purpose, no redundancy. Every sentence adds 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?
Complete for a simple search tool, but could explain 'conformance grade' and any query limitations. Still sufficient given no output schema.
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% for the single parameter; description adds extra detail (category) beyond the schema description, enhancing clarity.
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?
Clearly states the tool searches a registry for sites by capability, keyword, or category, and distinguishes from sibling tools which deal with sites directly.
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?
Provides clear context on what to search and how to invoke after discovery, but lacks explicit when-not-to-use or comparison with siblings.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Each tool has a clearly distinct purpose: searching capabilities, getting a site's capabilities, and listing all sites. No overlap in functionality.
All tool names follow a consistent verb_noun pattern with underscores: discover_capabilities, get_site, list_sites. The style is uniform and predictable.
Three tools is slightly low but appropriate for a read-only registry. The set covers the core operations: search, single lookup, and listing all entries.
The tool surface fully covers the apparent domain of querying the capabilities.txt registry. Includes search, site details, and site listing—no obvious gaps for read operations.