keyword_search

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

With no annotations, the description carries the behavioral transparency burden. It discloses meaningful matching behaviors beyond the schema, such as ALL-tag semantics, strict type matching in frontmatter, and websearch tsquery syntax. It stops short of explicitly stating read-only/non-destructive behavior, but the search characteristics and strict matching rules are well conveyed.

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 efficiently organized: a one-sentence purpose, a one-sentence routing instruction, then a terse Args list. Every sentence adds value, and the most decision-relevant information is front-loaded.

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 5-parameter search tool with no annotations, the description covers all parameters, explains the matching model, provides syntax guidance, and directs the agent to the correct sibling. The presence of an output schema means return-value documentation is not the description's responsibility, so nothing essential is 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 0%, so the description must fully compensate, and it does. Each parameter is explained with concrete examples: query syntax, folder prefix, limit default, tag AND-semantics, and frontmatter strict type matching. This adds substantial meaning over the bare schema properties.

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 and resource ('Full-text keyword search via PostgreSQL tsvector') and immediately defines the intended use cases: exact identifiers, code symbols, proper nouns, or known phrases. It also distinguishes itself from semantic_search, eliminating ambiguity about what this tool is for.

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 tells the agent when to use this tool versus an alternative: 'Use this for exact identifiers... For conceptual or paraphrased queries, use semantic_search instead.' This is direct, actionable routing guidance with no reliance on inference.

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