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

Beyond the annotations, the description discloses genuinely useful behavioral context: the output is 'heuristic indicators, not calibrated probabilities or a guarantee of safety,' that there are no model calls, and no automatic follow-on purchase. This clarifies the side-effect profile that the annotations (readOnlyHint=false, idempotentHint=false) only gesture at. It does not contradict them.

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?

Compact and front-loaded — the core operation leads, followed by constraints and caveats, with no filler sentences. The phrasing is slightly clipped ('$1 batch', stacked fragments), which costs a point but not clarity.

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?

An output schema exists, so return-format detail is unnecessary, and the description covers the key caveats and limits. Still missing enough for a 4–5: the role of agent_id, and any hint about what the indicator fields mean or how to interpret them.

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. It adds real semantics for 'texts' (batch of 1–20, 64 KiB total) and hints at 'session_id' via the 'verified fixed-order session' requirement, but says nothing about what 'agent_id' is or why it is required. Partial compensation only.

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 states a specific verb and resource: a batch of 1–20 text samples 'screened for deterministic injection markers.' That is more specific than the title alone and tells an agent exactly what comes back (heuristic indicators). It does not, however, differentiate itself from siblings like scan_source or security_preflight, so it stops short of a 5.

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?

Constraints are given (1–20 samples, 64 KiB total, 'Direct MCP requires the checkout caller and verified fixed-order session'), which implies when the tool is callable. But there is no explicit when-to-use guidance relative to scan_source or security_preflight, so routing among siblings is left to inference.

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