her_count_features

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

With no annotations, the description carries the full burden. It discloses speed ('fast'), that it avoids fetching full records, and that it returns counts grouped by designation type. It also notes the output can be json or text. While it doesn't cover error conditions, rate limits, or exact data structure, the provided behavioral traits are useful and non-contradictory.

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 and front-loaded with the purpose in the first sentence. It uses brief sections for Args, Returns, and Tips for LLMs, with every sentence adding value and no redundancy.

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 is a simple count operation with three optional parameters and no output schema, the description is complete. It covers purpose, parameter formats, return value summary, and practical tips for LLM usage (speed, use case, breakdown). No additional context is necessary for correct invocation.

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 fully compensates by explicitly explaining each parameter in the Args section: designation_type (filter, None for all), bbox (format 'xmin,ymin,xmax,ymax' in BNG), and output_mode (json default, text alternative). This adds meaning well beyond the bare 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 states a specific action: 'Fast count of heritage features in an area.' It clearly defines the resource (heritage features) and scope (area), and distinguishes itself by mentioning it returns counts by designation type without fetching full records, contrasting with sibling search tools.

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 usage guidance is provided: 'Use this before her_search_designations to estimate result sizes' and 'Use this to decide whether to narrow your search area.' It also mentions being 'much faster than a full search when you just need totals,' giving clear when-to-use versus alternatives.

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