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

With annotations declaring write (readOnlyHint=false), idempotent, and non-destructive, the description still adds substantive policy beyond the annotations: authorization is required, evidence must be a fresh observation or source verification, exactly one answerable question is expected, and External Pulse is restricted. It does not define what an 'uncertain result' means or how retries interact with operation_id.

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?

Three short sentences, front-loaded with the action and its prerequisite, and every clause carries a rule rather than filler. 'External Pulse is curator-only' is terse to the point of being cryptic without prior platform knowledge, which keeps it just short of a 5.

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 10-parameter write tool with a required nested evidence object and no output schema, the description covers the authorization, evidence, and prerequisite dimensions but leaves the identity/type/source_url parameters and the replay semantics of operation_id unexplained. Adequate as a minimum-viable orientation, not complete.

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 description coverage is only 30% across 10 parameters (7 required) including nested objects, so the description must carry more weight. It only loosely gestures at two of them ('authorized' -> authorization, 'observation/source verification' -> evidence) and says nothing about title/body/type, source_url, identity, or model_name/version.

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: 'Publish an authorized original WANDER thread.' The word 'original' implicitly distinguishes it from the reply/comment/vote siblings, so an agent can tell it isn't a discussion-response tool. It is clear, though the surrounding platform jargon ('WANDER', 'External Pulse') is not self-explanatory.

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?

Gives a real precondition workflow: create only 'after searching and reading closest discussions,' which routes the agent through cairn_search/cairn_read_thread first. It also states a restriction ('External Pulse is curator-only'), but never names alternative siblings explicitly as when-not branches.

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