Check whether a source URL is still live and how recently it was modified. Returns the HTTP last-modified header (if present), the most recent Wayback Machine snapshot, and a 'changed_recently' flag (last 90 days). Use this for RAG hygiene — flagging citations that point to pages that may have changed since the agent's training data.
| Name | Required | Description | Default |
|---|---|---|---|
| url | Yes | URL to check. |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries full burden. It discloses return values (last-modified, Wayback snapshot, flag) but omits potential side effects like network dependencies, rate limits, or error handling. Adequate but could be more detailed.
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?
Three sentences, each purposeful: first states purpose and returns, second details returns, third gives use case. No unnecessary words. Front-loaded with the verb.
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 a single parameter, no output schema, and no annotations, the description covers purpose, expected returns, and a concrete use case. Slightly lacking on potential failure modes or prerequisites, but still fairly complete.
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%, so baseline is 3. The description adds context about what is checked (live, modified) but does not add new meaning about the 'url' parameter beyond the schema's 'URL to check'.
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 'Check' and resource 'source URL', and clearly distinguishes from siblings (cite_check, fact_check) by focusing on liveness and modification. It also lists the exact return fields.
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 states when to use: 'for RAG hygiene — flagging citations...', providing a clear context. It does not explicitly exclude cases, but the specificity is sufficient.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Each tool has a clearly distinct purpose: cite_check verifies URL resolution and claim match, fact_check verifies factual claims against authoritative sources, and source_freshness checks URL liveness and modification date. No overlap or ambiguity.
All tools follow a consistent snake_case pattern with a verb (check, check, source) and noun (cite, fact, freshness), making the naming predictable and easy to understand.
With 3 tools, the server is well-scoped for its purpose of citation verification. Each tool serves a distinct function without being excessive or insufficient.
The server covers the core aspects of citation verification: URL validity, claim fact-checking, and source freshness. A minor gap might be the lack of a tool to retrieve citation metadata (e.g., author, date), but the current set is sufficient for typical use cases.