seo_keyword_density_checker

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

The description goes beyond annotations by stating that the tool is 'read-only, deterministic, non-destructive, contacts no external service, and is rate-limited.' It also outlines the tokenization process (Unicode-aware, optional stripping/stopword removal), adding valuable behavioral context that annotations alone do not provide.

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 informative yet efficient, covering purpose, usage, behavior, and parameter hints in a structured manner. It is slightly lengthy but every sentence adds value, so it earns a 4.

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 medium complexity and the presence of a comprehensive input schema and output schema (not shown but implied), the description covers all necessary aspects: input handling, processing details, output features, constraints, and sibling tool differentiation. It is fully complete for agent selection and 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 100%, so the schema already documents all parameters well. The description adds minimal extra semantic value for parameters (e.g., 'stopwords can be en, none, or custom array'), but it doesn't go into depth beyond what the schema provides, resulting in a baseline score of 3.

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 tool's purpose: 'Analyze plain text or HTML for keyword density and repeated phrases as an SEO content audit.' It distinguishes itself from sibling tools like text_word_frequency, text_text_statistics, seo_title_description_length_checker, and seo_meta_tag_generator, leaving no ambiguity about what it does.

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 tells when to use this tool ('when you need per-keyword and per-phrase density to detect keyword stuffing') and when to use alternatives (e.g., 'use text_word_frequency for a plain single-word frequency list'). This provides clear guidance for the agent.

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