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

Annotations already declare readOnlyHint, idempotentHint, non-destructive, and closed-world behavior, so the safety profile is covered. The description adds that output is validated against a bundled official XSD before returning and that the process is pure template rendering with in-memory validation, which is useful context beyond annotations, though it repeats the side-effect-free/idempotent claims.

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 well-structured with labeled sections (Purpose, When to use, When NOT to use, Behavioral transparency) and is front-loaded with the core action. Every sentence contributes directly to selection or invocation.

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 complex XML generation tool with an output schema already present, the description covers purpose, alternatives, prerequisites, validation behavior, and examples. It gives the agent enough to call the tool correctly without needing return-value details.

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%, and both parameters are described in the schema. The description adds little parameter-level meaning beyond what the schema already provides, though it reinforces that record fields should follow get_required_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?

The description states a specific verb (Generate), resource (schema-validated ISO 20022 E&I XML message), and concrete output examples (camt.056, camt.029). It clearly distinguishes itself from validate_xml and get_required_fields by naming them in the 'When NOT to use' section.

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 explicit when-to-use scenarios (payment cancellation, recall, investigation response) and when-not-to-use exclusions with named alternatives. The agent is told exactly which sibling to use for validation-only or incomplete-record cases.

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

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the description's 'pure, read-only, and idempotent' line largely restates structured data. It adds only the modest 'deterministic field dictionary lookup' framing, which is minor context rather than new behavioral disclosure.

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 one-line summary followed by labeled sections that scan quickly, and every section maps to a real decision the caller makes. The 'Behavioral transparency' block is somewhat redundant against the annotations, which slightly dilutes the otherwise tight structure.

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?

Covers purpose, prerequisites, exclusions, and example return content, and an output schema exists so return-value detail is not the description's burden. Complete enough to call correctly, with only the annotation-repeating section adding noise rather than gaps.

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 coverage is 100% for the single message_type parameter, and the schema already supplies the format example and the list_message_types pointer. The description adds no syntax or format detail beyond the schema, so the 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 (get) and resource (required schema fields) scoped to ISO 20022 E&I message types, and names the sibling tools (generate_message, list_message_types) that bound its role. An agent can distinguish it from list_message_types or generate_message without opening any schema.

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?

Explicitly enumerates when to use it (preparing payloads before generate_message, validating completeness before XML serialization) and when NOT to use it, pointing to list_message_types for discovering supported types. This is a full when/when-not/alternative routing statement.

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

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint=false, and destructiveHint=false, so the safety profile is covered. The description still adds that this is a 'static catalogue retrieval,' which tells the agent the result set is stable and cacheable. However, 'pure, deterministic, side-effect-free' largely restates what the annotations already say, so it is useful but partly redundant.

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 the core statement and then cleanly sectioned, so it scans well. The 'Purpose:' block largely restates the opening sentence and the behavioral block repeats annotation content, so a little trimming is possible, but nothing is confusing or buried.

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?

A zero-parameter, read-only catalogue tool with an output schema and full annotation coverage needs nothing more. The description covers what is returned conceptually, when to call it, and when to avoid it, so an agent has everything required to invoke 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?

The tool takes zero parameters, so the baseline is 4. The description's framing (discovering valid message_type values) is contextually useful even though there is nothing parameter-wise to document.

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 ('List supported ISO 20022 E&I message types') and pins the domain down with concrete examples (camt.056.001.12, camt.029.001.14). An agent can immediately tell this is a catalogue-listing tool rather than a generator or validator, which is exactly how it differs from its siblings.

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?

Explicit 'When to use' and 'When NOT to use' sections, and the exclusions name concrete alternatives (pain initiation, camt.053 statements). The positive cases — discovering valid message_type values and verifying schema version support — give the agent a clear trigger condition.

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

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

Annotations already declare readOnly, idempotent, non-open-world, non-destructive. The description adds genuinely new context: pure in-memory validation with locally bundled XSDs and zero network access or side effects. It stops short of describing diagnostics detail, but the output schema covers returns.

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?

Labeled sections (Purpose, When to use, When NOT to use, Behavioral transparency) make it scannable and front-loaded, though the header scaffolding is slightly heavier than strictly needed for a two-parameter 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?

An output schema exists so return values need not be explained. With safety covered by annotations, parameters by the schema, and scope/limits by the description, an agent has everything needed to invoke 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 both parameters are already documented, and the description adds no format or syntax detail beyond what the schema states. Baseline 3 applies when the schema carries the parameter burden.

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+scope: validating raw ISO 20022 E&I XML against bundled XSD schemas. Clearly distinguishes itself from siblings like generate_message and list_message_types, which produce or enumerate rather than validate.

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?

Explicit when-to-use (pre-ingest inspection, diagnosing structural/datatype/constraint errors) and when-not-to-use (pain/camt.053 documents, binary content). Also points to list_message_types for valid message types, giving the agent a routing path to the sibling.

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