Retrieve the full list of federal agencies publishing in the Federal Register, with names, short names, slugs, and URLs for filtering and lookup.
List all federal agencies that publish in the Federal Register. Returns agency names, short names, slugs (for filtering), and URLs. 470+ agencies.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v2026.4.11Input schema / additionalPropertiesRemoved value: -falsev2026.3.9Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds the scope ('all federal agencies that publish in the Federal Register') and the count ('470+'), which is useful context. It does not disclose pagination or response size limits, but for a simple list tool this is a minor gap.
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?
Two sentences with no filler. The core purpose is front-loaded, and the return fields and scale are stated compactly. Every sentence earns its place.
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 zero-parameter, read-only list tool with no output schema, the description covers the essential facts: what is listed, what fields are returned, and the approximate size. It could mention pagination or how to use slugs, but the description is complete enough for an agent to invoke it correctly.
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 tool has zero parameters, so the schema provides no parameter semantics. The description compensates by explaining what the returned data contains (names, short names, slugs, URLs), which is the only meaningful semantic information an agent needs. Baseline 4 for zero-param tools 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 states a specific verb ('List') and resource ('all federal agencies that publish in the Federal Register'), and specifies the returned fields (names, short names, slugs, URLs). It is clearly distinguishable from sibling tools like fbi_agencies or fr_search_rules.
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 implies this is a reference/list tool for enumerating agencies, and the mention of slugs 'for filtering' hints at downstream use. However, it does not explicitly state when to choose this over alternatives or provide exclusions. For a zero-parameter list endpoint, this is adequate but not explicit.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.