Fetch the HTTP response headers for a URL.
| Name | Required | Description | Default |
|---|---|---|---|
| url | Yes | Full URL, e.g. https://deinkunde.com |
| Name | Required | Description | Default |
|---|---|---|---|
| ok | No | ||
| url | No | ||
| status | No | ||
| headers | No | ||
| redirects | No | ||
| statusText | No |
Changes observed during successful MCP inspections. Dates show when Glama detected each change.
Output schema / (root)Previous value: -nullNew value: +{
+ "$schema": "http://json-schema.org/draft-07/schema#",
+ "additionalProperties": {},
+ "properties": {
+ "headers": {
+ "anyOf": [
+ {
+ "additionalProperties": {
+ "type": "string"
+ },
+ "propertyNames": {
+ "type": "string"
+ },
+ "type": "object"
+ },
+ {
+ "type": "null"
+ }
+ ]
+ },
+ "ok": {
+ "anyOf": [
+ {
+ "type": "boolean"
+ },
+ {
+ "type": "null"
+ }
+ ]
+ },
+ "redirects": {
+ "anyOf": [
+ {
+ "items": {
+ "additionalProperties": {},
+ "properties": {
+ "from": {
+ "anyOf": [
+ {
+ "type": "string"
+ },
+ {
+ "type": "null"
+ }
+ ]
+ },
+ "status": {
+ "anyOf": [
+ {
+ "type": "number"
+ },
+ {
+ "type": "null"
+ }
+ ]
+ },
+ "to": {
+ "anyOf": [
+ {
+ "type": "string"
+ },
+ {
+ "type": "null"
+ }
+ ]
+ }
+ },
+ "type": "object"
+ },
+ "type": "array"
+ },
+ {
+ "type": "null"
+ }
+ ]
+ },
+ "status": {
+ "anyOf": [
+ {
+ "type": "number"
+ },
+ {
+ "type": "null"
+ }
+ ]
+ },
+ "statusText": {
+ "anyOf": [
+ {
+ "type": "string"
+ },
+ {
+ "type": "null"
+ }
+ ]
+ },
+ "url": {
+ "anyOf": [
+ {
+ "type": "string"
+ },
+ {
+ "type": "null"
+ }
+ ]
+ }
+ },
+ "type": "object"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations declare readOnlyHint=true, and the description's 'Fetch' aligns with this read-only behavior. However, the description does not disclose any behavioral nuances such as redirect following, timeouts, or rate limits, so it adds only minimal context beyond the annotation.
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 entire description is an eight-word sentence that states the core function without redundancy. It is appropriately sized for a one-parameter read-only tool and front-loads the key information.
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 tool with a single required parameter, full schema coverage, a readOnly annotation, and an output schema, the description is sufficiently complete. No additional context is necessary for an agent to select and invoke it 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?
The input schema already documents the only parameter (url) with format guidance ('Full URL, e.g., https://deinkunde.com'), providing 100% coverage. The description adds no parameter-specific details beyond referring to 'a URL,' so baseline 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 ('Fetch') and resource ('HTTP response headers'), clearly identifying what the tool does. It also distinguishes this tool from siblings like check_ssl or whois by focusing on HTTP headers.
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?
No guidance is provided on when to use this tool vs alternatives. The description only states the action and target, with no mention of when it's appropriate, prerequisites, or exclusions.
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.
Several tools cluster around overlapping diagnostics, such as asn_lookup vs ip_geolocation and website_status vs response_time/redirect_check/http_headers. Descriptions generally clarify the differences, but the boundaries between some tools are not immediately obvious.
Naming conventions are mixed: check_dns and check_ssl use verb-first, while dkim_check, spf_check, and hsts_check use noun-first. There are also varied styles like dns_propagation, domain_expiry, and whois, making the pattern inconsistent but still readable.
At 20 tools, the server falls into the borderline heavy range. Most tools address a distinct diagnostic need, but some could be consolidated, such as website_status overlapping with response_time and redirect_check.
The toolkit covers the core read-only network/domain diagnostic domain well: DNS, email authentication, SSL/TLS, WHOIS, IP intelligence, and website availability. Minor gaps like traceroute or DNSSEC validation exist, but there are no critical missing operations for the apparent purpose.