residency_check

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

With no annotations provided, the description carries the full responsibility for behavioral disclosure. It explains an important semantic subtlety: a null result from an evicted cache is not an all-clear, and it defines what `failed` means. It does not mention side effects, permissions, or other possible return states, but the key interpretability trap is clearly surfaced.

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 description is compact, with two sentences that each add value: one defines the core question and failure semantics, and the other names the required dependency. The rhetorical question is slightly less direct than an explicit imperative, but the description remains tightly structured and free of filler.

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 four-parameter tool with no annotations and no output schema, the description is incomplete: it explains the failure case but not what a successful or interpretable outcome looks like, nor what the parameters mean. It provides purpose, one dependency, and one important semantic caveat, but that is not enough for an agent to invoke the tool correctly with confidence.

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 0%, so the description must compensate for the lack of parameter documentation, but it does not explain `model`, `kv_budget_gib`, `n_prefixes`, or `tokens_each`. The cache-probe context hints at the role of `kv_budget_gib`, but an agent would struggle to know what values to supply for the two required parameters and how the optional parameters affect the check.

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 clearly identifies the tool as a check on whether a cross-tenant cache probe result can be interpreted, and it specifies a concrete output condition: `failed` when the victim's state could not have stayed resident. It is not a bare tautology and conveys a distinct domain purpose. However, it is phrased as a question rather than a direct verb phrase and does not distinguish itself from sibling tools like `lean_check` or `gate_count`.

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 description gives one operational prerequisite, `Requires kvleak`, which tells the agent that this dependency must be available before calling. The intended use case is implied: use it when you need to know whether a cross-tenant cache probe's result is interpretable given residency. It does not explicitly state when to prefer this over alternatives or when not to use it.

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