Find and run trustworthy calculators with clear methods, provenance, and sources.
Scored across 3 tools
The three tools target clearly distinct lifecycle stages: search_calculators discovers, get_calculator_schema inspects the contract, and run_calculator executes. There is no overlap in purpose, and an agent can trivially pick the right tool.
All three follow a clean verb_noun snake_case pattern (search_calculators, get_calculator_schema, run_calculator). The only minor deviation is singular 'calculator' in two names versus plural in the search tool, but the convention is otherwise predictable.
Three tools is well-scoped for a calculator catalog: each maps to one essential step (discover, inspect, run) with no redundant or filler tools. Nothing feels missing or excessive for this narrow domain.
Discovery, schema inspection, and execution cover the full consumption workflow, and search's optional category plus schema/version resolution round it out. There is no authoring or listing-all capability, but that appears outside the stated read/run scope, so only a minor gap remains.
Get the input and output schema for a calculator, generated from its reviewed contract: parameter types, units, allowed dropdown values and definitional bounds, plus outputs keyed by named range (including the status output). Table inputs carry a 'grid' block giving the exact number of rows to send, the column layout, which columns are editable, and how to shape a row; a table whose 'grid' block says writable=false cannot be supplied at all. Schema 0.18 exposes required and omitted declarations plus version-bound visibility tables; older versions require every input while awaiting metadata migration. Optionally resolves one immutable platform version. Returns trust metadata for the resolved version.
| Name | Required | Description | Default |
|---|---|---|---|
| slug | Yes | The calculator slug, e.g. 'steel-column-capacity-calculator'. | |
| platform_version | No | Optional positive platform version number. Omit for the current published version. |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden, and it delivers: it discloses the writable=false table constraint, the pre-0.18 'every input required' behavior versus 0.18's required/omitted declarations, and that it returns trust metadata for the resolved version. It doesn't cover auth requirements or rate limits, keeping it below a 5.
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?
Front-loaded with purpose, then details about the returned schema structure and version behavior. Dense but every clause adds information; the middle sentence about 'grid' blocks is long but earns its place for a schema-inspection tool.
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?
No output schema exists, so the description must characterize returns — and it does, describing parameter types, units, dropdown values, bounds, named-range outputs, the status output, and grid blocks. It also covers the version-visibility caveat. Minor gaps remain (no example call, no errors), but the return-shape coverage is notably thorough.
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 100% — both slug and platform_version are fully documented in-schema, including the 'omit for current published version' default and the 'must be positive' constraint. The description adds only the 'one immutable platform version' framing, so baseline 3 applies.
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+resource ('Get the input and output schema for a calculator') and names the source of truth ('generated from its reviewed contract'). This unambiguously distinguishes it from run_calculator (execute) and search_calculators (discover).
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 implies this is the inspection step before invocation, and mentions the optional platform_version resolution, but never explicitly states when to call this versus run_calculator or how it fits a workflow. Usage is inferable rather than spelled out.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Run a calculator with the given inputs. Inputs are validated against the resolved version's reviewed contract and computed by SpreadsheetWeb through the same proxy as the web channel. An optional platform_version pins both validation and computation to that immutable version. Returns outputs keyed by named range (including the status output) and trust metadata with a citation URL, resolvedInputs, and warnings for omitted inputs. Missing or blank visible required inputs are refused before computation; inspect get_calculator_schema and the complete error detail. For schema 0.18, optional omissions are sent explicitly as declared blank or standing default and disclosed with their values and sources. Older pinned contracts require all inputs during migration. Visibility follows version-bound truth tables over dropdown options, or over blank/set for a clearable optional input (omitted, null or whitespace is blank; 0 is set); a missing required controller makes its dependents indeterminate until it is supplied. A hidden controller is ignored only when all of its option branches have the same remaining visibility subtree; otherwise its dependents stay hidden. Hidden omissions use explicit blank/default values; supplied hidden inputs are retained with a not-applicable warning. Always read Model_Status and status outputs; CHECK and STOP are load-bearing verdicts about the result's validity. Results are informational and not professional advice; the applicable notice is returned in the trust block.
| Name | Required | Description | Default |
|---|---|---|---|
| slug | Yes | The calculator slug. | |
| inputs | Yes | Input name/value pairs matching the calculator schema (from get_calculator_schema). A table input takes a list of rows matching its 'grid' block exactly; a table of the wrong extent or shape is refused rather than partially applied. | |
| platform_version | No | Optional positive platform version number. Omit for the current published version. |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden and delivers rich detail: refusal of missing/blank required inputs before computation, trust metadata with citation URL/resolvedInputs/warnings, visibility truth-table semantics, hidden-controller handling, and CHECK/STOP verdicts. This far exceeds a minimal safety statement and discloses exactly what gets validated, retained, or flagged.
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 purpose is front-loaded in the first sentence, and most content is load-bearing given a complex calculation engine. However, the description is a dense, unstructured wall of run-on sentences covering visibility truth tables and migration edge cases, which is hard to parse and could be trimmed or segmented.
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?
There is no output schema, and the description compensates thoroughly by describing return values (outputs keyed by named range including status, plus a trust block with citation URL, resolvedInputs, and warnings). For a nested-input, version-pinned calculation tool, an agent has everything needed to invoke and interpret it 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 100%, so the baseline is 3, but the description adds real meaning beyond the schema: platform_version pins both validation and computation to an immutable version, and inputs are validated against a reviewed contract with table-shape refusal. These are semantic constraints the schema only gestures at.
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 opening sentence states a specific verb (run) and resource (calculator) with explicit inputs. It further clarifies that validation and computation happen through a proxy against a resolved version contract, which distinguishes it from the sibling get_calculator_schema. It stops short of explicitly naming when to prefer it over siblings, but the core purpose is unambiguous.
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?
It gives concrete operating guidance: inspect get_calculator_schema first, always read Model_Status and status outputs, and note that pinned older contracts require all inputs during migration. It does not explicitly frame a when-not-to-use or a direct A/B choice against siblings, but the conditional behaviors amount to clear usage context.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Search the LogicCommons calculator catalog by keyword and optional category. Returns matching published calculators with slug, name, summary, category, a citation URL, and trust metadata.
| Name | Required | Description | Default |
|---|---|---|---|
| query | Yes | Free-text query matched against calculator name, summary and category. Empty returns the catalog. | |
| category | No | Optional category slug to filter by, e.g. 'structural-civil'. |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden; it discloses that only published calculators are returned and that results carry trust metadata and a citation URL, which is useful. However, it says nothing about pagination, result limits, or auth requirements for a catalog search.
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?
Two sentences, zero filler, with the core action and scope front-loaded before the return-value summary. Every clause earns its place.
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 simple two-parameter read search with no output schema, the description usefully enumerates the returned fields (slug, name, summary, category, citation URL, trust metadata). Only pagination/limit behavior and explicit sibling routing are missing.
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 100%, so both parameters are already fully documented, including the empty-query behavior and the category slug example. The description only restates 'keyword and optional category' and adds no syntax or matching semantics beyond the schema.
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 names a specific verb (search) and resource (LogicCommons calculator catalog) and scopes it by keyword and category. It is clearly distinguishable from a schema-fetch or execution tool, though it never names its siblings get_calculator_schema/run_calculator to draw the boundary explicitly.
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 when-to-use or when-not-to-use guidance and no mention of the alternative sibling tools. The only usage hint ('Empty returns the catalog') lives in the schema, not the description.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Recent tool additions, removals, and schema changes observed during successful MCP inspections.
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