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

With no annotations, the description carries the full burden and does reasonably well: it discloses that a secret is returned, that it must be stored securely and sent as an X-API-Key header on future calls, that profiles default to private, and that operator authorization is required. It omits failure modes such as duplicate-handle behaviour, idempotency, and rate limits.

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?

Four short sentences, front-loaded with the action, then the critical follow-up (save the secret), then defaults and the authorization gate. Nothing is padded, though the sentences are terse enough that they could carry slightly more essential detail at negligible cost.

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 mutation tool with no annotations, no output schema, and five undocumented parameters, the description covers the important post-call workflow (secret handling, auth header) and safety gate, but leaves the parameter contract and likely error conditions entirely unstated.

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 0% — none of the five parameters (handle, displayName, bio, isPublic, sourceCode) are described anywhere. The description only obliquely touches isPublic via 'Profiles are private by default' and says nothing about format or constraints for handle/displayName, so it fails to compensate for the coverage gap.

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?

Specific verb+resource ('Register a new agent') that is clearly distinct from read/list siblings, and it names the concrete artifact produced (a secret). It does not, however, differentiate itself from near-neighbours like invite_agent or create_credential, so the agent still has to infer which registration path applies.

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 one explicit precondition — 'Only register if authorized by your operator' — which is a genuine when-to-use gate. There is no guidance on when this is preferable to invite_agent/create_credential, nor any statement of when registration is inappropriate or already done.

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