ms_geology_place_counterions

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

With no annotations provided, the description carries the full burden. It implies a mutation operation ('Place') but does not disclose effects, idempotency, reversibility, or whether the ledger review is a mandatory precondition. The idempotency_key parameter is not mentioned, and the operation's impact on the existing structure is unclear.

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 a single, efficient sentence with no redundancy, which is positive. However, given the tool's complexity (12 parameters, no annotations), this is under-specification rather than appropriately sized. It is not as extreme as a tautology, but lacks necessary detail.

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?

The tool has 12 parameters, no annotations, and an output schema that is not described. The description provides no workflow context, prerequisites, or guidance on how this fits into the broader pipeline (as seen in sibling tools). It is insufficient for an agent to select and invoke the tool correctly.

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%, and the description provides no information about any of the 12 parameters (e.g., placements, min distances, output_slot, max_atoms). The only vague hint is 'reviewed P1 fractional-coordinate ledger', which could relate to input_structure or placements but is not mapped explicitly.

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 states the action ('Place explicit counterions') and the source ('a reviewed P1 fractional-coordinate ledger'), which conveys a specific scope. However, it does not explicitly differentiate this from sibling geology tools like ms_geology_apply_substitutions or ms_geology_apply_hydroxylation_ledger, beyond the mention of the ledger.

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?

There is no guidance on when to use this tool versus alternatives, nor any mention of prerequisites, expected inputs, or exclusions. The 'reviewed ledger' implies a prior review step, but this is not elaborated.

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