validate_template

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds useful behavioral context by specifying what constructs are validated and that it reports missing keys, going slightly beyond the structured annotations without contradicting 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?

The description is two sentences with no filler. It front-loads the core purpose, states the safety guarantee, and gives actionable usage guidance. Every sentence 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?

Given the tool has rich annotations, a complete input schema, an output schema, and a clear relationship to fill_template, the description covers purpose, timing, and safety sufficiently. No critical context is missing for an agent to select and invoke this 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 100%, with both parameters already described clearly in the input schema: data is 'Key-value data to validate against placeholders' and template_path is 'Path to the template document (.docx/.xlsx).' The description does not add significant parameter-level detail beyond what the schema provides, so the baseline of 3 is appropriate.

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 uses a specific verb ('Validate') with a clear resource ('template') and enumerates exactly what is checked ({{placeholder}} variables, {{#each}} loops, {{#if}}/{{#unless}} conditions). It also states the outcome ('reporting missing keys') and distinguishes itself from fill_template by name.

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 explicitly says 'Call this BEFORE fill_template to catch missing keys early,' giving clear when-to-use guidance and naming the related alternative tool. It also clarifies the read-only nature, reinforcing that this is a pre-flight check rather than a mutation operation.

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