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

With no annotations provided, the description carries the full burden and does well: it discloses side effects (temporary, low-confidence entries, 48h TTL), the isolation guarantee, and the response shape. The gap is what happens at TTL expiry (auto-delete vs. flag) and whether any auth or permission constraints apply.

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 purpose and bracketed with the vault context, then scope, return value, and side effects. Only mild cost is jargon density ('Zone 2 Hypothesis (v0.1)') that a new agent must decode from context.

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 3-parameter write tool with no annotations and no output schema, the description supplies the safety profile (private, isolated, TTL-limited) and the return shape, which is most of what an agent needs. Remaining gaps are TTL expiry semantics and permission requirements.

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?

At 67% schema coverage, title and content are documented but tags has no description anywhere. The description adds no parameter-level meaning at all — no tag format, no size limits, no guidance on how title/content should be phrased for a hypothesis. It neither compensates for the gap nor reinforces the documented fields.

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 ('Store an unverified claim as a Zone 2 Hypothesis') and pins the scope with 'Isolated from formal facts', which implicitly separates it from vault_write_cell-style formal writes. It never names a sibling tool for contrast other than the downstream promote_hypothesis, so the differentiation is inferred rather than explicit.

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 lifecycle is clear: use this for unverified claims, and route to promote_hypothesis once verified. 'Prevent vault pollution' conveys the reason and thus the when-not-to-use. It stops short of naming the formal-write alternative or listing explicit exclusion cases.

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