list-auth-identities

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

With no annotations, the description carries the full burden and does well: it discloses the exact return projection ({provider, email, username, linked_at}) and the sanitisation/filtering behavior at the SDK boundary, which is meaningful context an agent could not infer. It omits read-only confirmation and any auth/rate-limit notes, keeping it short of a 5.

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?

Front-loaded with purpose and return shape in the first two sentences; the third sentence adds useful behavioral context but drifts into meta-commentary about the SDK's future-proofing ('a future server-side change can never leak through a tool surface'), which is less relevant to tool selection.

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?

There is no output schema and no annotations, yet the description fully compensates: it names the returned fields, explains the sanitisation behavior, and contrasts with the sibling tool. An agent has everything needed to call this zero-arg tool and interpret its result.

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 takes zero parameters, so there is no parameter semantics to explain and the baseline of 4 applies. The description correctly does not invent parameters or imply optional filters.

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?

States a specific verb and resource ('List the external identities linked to the current syntx.ai account') and immediately names the sibling it differs from: the per-provider breakdown that 'get-profile' does not carry. An agent can distinguish it from get-profile and whoami without opening any schema.

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 phrase 'the per-provider breakdown that get-profile does not carry' effectively tells the agent when to pick this tool over get-profile. However, it never states an explicit when-not or what get-profile should be used for instead, so the routing is clear but not fully spelled out.

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