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

Annotations already declare readOnly, idempotent, non-destructive and openWorld, so the safety profile is covered; the description adds real context by naming the required HGRApi header channel / ChannelOAuthId. It also flags the endpoint is fixed, which bounds the tool's behavior. The statement that ChannelOAuthId is 'resolved internally' sits oddly against a schema that makes it a required parameter, leaving the auth model slightly ambiguous.

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 Purpose/Use when/Input/Output/Search terms structure is front-loaded and easy to scan, but the second sentence ('explicit tool with a fixed endpoint; it is not a generic endpoint caller') and the 'Search terms' line are filler that adds no information an agent can act on.

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?

An output schema exists, so return values need not be described, and the parameters are fully covered by the schema. However, for a tool whose name is opaque jargon, the description never explains what the 'go out' operation actually accomplishes, when the result would differ from the plain hgr_get_sources call, or what the empty/error cases look like — the essential piece of context is missing.

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%, so the schema already documents all four parameters and the baseline is 3. The description's 'Input:' line enumerates only the three query parameters and omits channelOAuthId, the very parameter it claims is 'resolved internally' — it adds no semantics beyond what the schema provides and slightly muddies the required-parameter story.

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 identifies the verb and endpoint (GET api/Sources/GoOut) and scopes it to 'source/supplier reading', but the core concept 'go out' is never explained, so an agent cannot tell what distinguishes this from hgr_get_sources, hgr_get_sources_get, or hgr_get_sources_getpublic. It also spends a sentence ruling out a nonexistent confusion ('not a generic endpoint caller') instead of differentiating from its actual siblings.

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 'Use when' clause is circular: 'Use it when a client needs to run the go out operation' restates the tool name rather than giving a selecting condition. No alternative tools are named, no prerequisites are stated, and no exclusions are given despite three closely named sibling tools that would be natural alternatives.

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