registry_list_agents

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

No annotations are provided, so the description carries the behavioral disclosure burden. It clearly indicates a read-only list operation with optional filtering, but does not disclose details like tag matching semantics, pagination, ordering, or behavior when no tag is provided.

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 a single, front-loaded sentence with no filler. Every word contributes meaning, and the optional filter is cleanly integrated as a parenthetical.

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?

This is a simple listing tool with one optional parameter and an output schema available, so the description covers most operational needs. It would benefit from explicit guidance on tag matching or alternatives, but the lack is minor given the low complexity and existing 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?

The schema only defines the tag parameter as a nullable string with a default of null. The description adds meaning by stating the tag is used for filtering, which is essential functional context beyond the raw schema.

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 action ('List') and resource ('registered agents'), and notes the optional tag filter. This clearly distinguishes it from sibling tools like registry_get_agent (single fetch) and sessions_list_agents (session-scoped agents).

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 purpose implies when to use it: when you need to enumerate registered agents or filter them by tag. However, it does not explicitly mention alternatives or when not to use this tool, so guidance remains implicit rather than explicit.

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