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

The annotations already mark the tool as readOnly, idempotent, and non-destructive. The description adds valuable context beyond annotations: presets are not platforms and never count in summary.total (CO 455), and the same call works at every depth. This explains edge-case behavior without contradicting the annotations.

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 dense but every sentence earns its place. It front-loads the core purpose ('Browse... recursive catalog'), then explains side, presets, parent, relationship to sibling, return structure, and an example call—all without redundancy. The length is justified given the tool's recursive nature and missing output schema.

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 description is fully complete for this tool: it explains navigation (top-level vs parent), side filtering, presets (what they are and how they affect counts), return shape with exact fields, and the relationship to agents. Since there is no output schema, the description carries the burden of return-type explanation, and it does so thoroughly.

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 provides full coverage of both parameters, giving baseline 3. The description adds concrete meaning with examples: side='vendor' returns sell-on platforms (retail, bookings, services) and side='customer' returns run-with tools (messaging, shipping, marketing). For parent, it gives an example of parent='messaging' returning channels (email, sms, dm), and notes that side is ignored when parent is present (also in schema). This enriches the parameter understanding.

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 the tool 'Browse the ComOS network's composable platforms as a recursive catalog' with a specific verb and resource. It also distinguishes itself from the sibling federation_catalog_agents by explaining the difference: 'platforms are what you become; agents are the operators you hire to run them.'

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?

It explicitly names an alternative tool (federation_catalog_agents) and contrasts when to use which. It also indicates the tool 'answers an agent shopping the network' and works at every depth, providing clear usage context. The side parameter semantics (vendor vs customer) are explained with examples, leaving no ambiguity about when to use the tool.

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